Trucks are Tree Tubes Too!

"Perhaps one in a billion seeds becomes a mature tree." Dr. Edward F. Gilman

So what does that have to do with an ugly boxelder tree growing through the rotted out floor of a Dodge pickup truck? Glad you asked.

The first sentence in Dr. Edward Gilman's brilliant article Roots of change for the better has the "billion to one-shot" claim for a seed. He goes on to list many of the hurdles a tree seed faces trying to get established. We seel product to overcome those problems at www.plantra.com. With this post I want to talk about where that billionth seed must grow to become a tree.

Seeds are tasty and need protection from herbivores. Seedlings are delicate and also need shelter from drying winds and intense sunlight. Some of the problems a seedling faces include rodents, rabbits, deer, wind, and drought. A tree seedling needs enough sunlight for photosynthesis but it cannot compete out in the open for water and sun with grasses and weeds.

Where can a poor defenseless seed find a place in nature to germinate that provides all that protection to overcome the billion to one odds? This magical or miracle location must be free of seed eating animals, protected from rabbits and deer, partially shaded against the drying sun, and not have competing weeds. Now we know why trees play the odds and produce so many seeds.

My two favorite examples are rock crevices and the brushy tops of fallen trees. Hard to imagine those two environments have anything in common, but both have the potential under ideal weather conditions to protect and nurture a seed.

A seed in a rock crevice is partially shaded and has all the moisture in the crevice for itself. What about rodents? Well, voles and mice will not leave the cover of weeds. Why? Because rodents fear death from above brought by raptors. While there might be some weeds in the rock crevice, a thin line of grass does not provide attractive cover for rodents. So hard as it is to believe, a crack in a rock can be a great place for a tree to start life. Took the picture below last spring in Colorado outside of Estes Park. And yes that tree is growing straight out of a rock - as were many others in the area.

Why is a fallen tree top a great place for a seedling? Remember we are talking billion to one shot odds, so it is OK to line up the coincidences.

Many seeds need contact with mineral soil or bare dirt to germinate. What better way to scrape away some leaf duff on the forest floor than branches crashing to the ground? Big animals such as deer cannot penetrate the dense mass of compressed branches protecting our new seedling.

Voles are likely to seek the raptor free shelter of a fallen tree, so how do our fortunate seed and seedling survive? Good shelter is hard to find and our lucky brush pile is also home to a family of snakes, or skunks if you prefer. We don't have to kill all the rodents to grow a tree. We just have to give them a good reason to go elsewhere. Snakes are a great reason for mice to go elsewhere and snakes don't eat trees.

What about weeds? A forest floor has inches of natural mulch to block weeds. Our tree seed is in a small spot where the mulch was scraped away. It will take a while for the small forbs to get through the duff (mulch) and catch up to the larger tree seedling.

Underneath the truck bed it is weed free, protected from drying sun and wind. The seed germinates and the radicle grows directly into mineral soil. The truck bed provides cover for a carnivore that keeps the rodents away. There is a small gap in the rotting floor boards. The light seeking apical meristem pours all the available energy into growing through that gap and into the sunlight. It still has to get past the deer. Our fortunate seedling is protected by the structure of the pickup bed.

While keeping four hooves on the ground the deer mouth can only reach so far in and our box elder is just out of reach. Now if box elder was something the deer really wanted or the deer was starving the it could jump right up in the pickup bed. Fortunately box elder is mostly unwanted by man and deer - so it thrives.


Below is a copy of our Stages Of Seedling Establishment available on our website at the link. It is amazing to me how a crack in a rock, an abandoned Dodge pickup truck, a brush pile and a tree tube all provide the nurturing micro-environment a seed needs to overcome the nearly insurmountable odds to become an established tree.

Mitzi and the Zombie Trees

Last summer my wife and I were on vacation in St. Louis.

We stopped at the gateway arch to take pictures inside and out. While walking around the park under the arch, I noticed a clump of ash that could provide some welcome shade. What I found was a whole stand of zombie trees. The living dead.


The ash above is in a death grip. A death grip of circling roots girdling the tree.

Girdling roots are a common problem transplanted trees such as B&B or balled and burlap trees. Planting large trees like this means you are likely to get a damaged root system and a short life span. Planting small seedlings avoids this problem and grows a tree in place with a natural root structure and the potential for a long life.

The young oak below was planted as a seedling at Lincoln's Tomb in Springfield, IL. Notice the radial root supporting the oak. The folks managing Lincoln's Tomb want oaks and they want oaks that will live well over 100 years.


This oak tree was protected with a tree tube or tree shelter when planted. That is the secret - use a Plantra Tree Tube and plant small seedlings to produce a normal root system that will support your tree for 100 years or more.

If you want more information on trees and root systems in landscapes go to Ed Gilman's web page hosted by the University of Florida.

The Great Central High School Tree Planting

Back in July I put together a post on the Great Central High School Urban Reforestation. Since then I have scanned 70 pictures from the original planting and learned a great deal from the woman responsible for it.

There are so many interesting things about this project I plan to break it into bits.

To me the most amazing thing about this planting is that a grove of bur oaks or any tree for that matter could start out as a tiny seedling. Those trees were seedlings in a bucket in 1991. The reason we can enjoy them today is that Bonnie Lawrence had the forsight and courage to put them in tree tubes.

This is what it looked like at the start.

I wonder how fast they would have grown in a good year?

Joe and I just made a visit to Ottertail Cty, MN that closed the book on another great year of collaboration with Babe Winkelman, host of Good Fishing and Outdoor Secrets and - just as importantly in Babe's mind - steward of a property he is working (man, is he working!) to enhance for wildlife and pass down to his children & grandchildren.

Working with Babe, his wife Kris and his staff has been one of the real highlights of Plantra's history.

Plantra Tree Tubes were recently featured on an episode of Outdoor Secrets. To view the video, Click Here.

We have actually undertaken 4 projects at Babe's ranch. Keep in mind that Ottertail Cty, MN - despite its 1100+ lakes (yes, that's more than 1000 lakes in a single county!) is generally dry & windy; it's right on the edge of where the hardwood forest meets the prairie, which means it's right on the line to the west of which annual evaporative potential exceeds rainfall - especially in recent years.

1) Planting 1500 new crabapple seedlings in 4 soft mast "overhead food plots." In May 2008 seedlings (bare root 1-0 planting stock, 6 to 12 inches tall at planting time) were machine planted by the local conservation district. Six foot wide woven weed barrier fabric was installed by machine over the seedlings. We then installed 5 foot Plantra O-style Vented Tree Tubes on all of the seedlings.

So now the trees have 2 growing seasons under their belt. Recently the staff of the local NRCS office toured the ranch. They took this photo (click to enlarge).

The gentleman in the photo is more than 6ft tall... which puts these 17 month old crabapples at 8-10 feet in height. And as you can see, that level of growth is consistent throughout the food plot.

Survival? As of last count fewer than 30 trees out of those 1500 have been replaced, a survival rate of 98% under tough, windy conditions.


2) Rejuvenating a failed hedgerow of Nanking cherry, American plum and assorted other fruit-bearing shrubs and small trees. Over the course of 6 years Babe has planted more than a mile of hedgerow to provide food, cover and edge effect/travel corridors for wildlife. I should say he planted, replanted, and replanted again. After 5 years Babe had nothing to show for his efforts - at least at first glance. He pointed to the hedgerows and all you could see was 2ft tall grass. A closer look revealed hundreds - thousands - of surviving seedlings that had been kept mowed in bonsai fashion to about ankle or shin height. Babe was stuck. You couldn't see where the seedlings were so you couldn't mow or spray around them. And without protection they would never grow past the browse line.

In late May, 2008 we selected a 3/8 mile section of the hedgerow to start with. 4 foot Plantra O-style Vented Tree Tubes were applied. We have a saying at Plantra: "As long as you have a root system, you have a tree." These trees had root systems that were 3, 4 and 5 years old, a huge amount of growth potential just waiting to be unleashed... and man was it unleashed!

The first plants started emerging from the 4ft tubes on June 25 - just 5 weeks later! Here's what the hedgerow looked like as of July 3, 2009 (click photo to enlarge). After a cool July but a somewhat warmer August, the trees are even bigger now.

It's obvious how the Plantra Tree Tubes protected the trees from deer browse, and how they shielded the plants from the drying effects of the wind to keep them actively growing when un-tubed trees would have stop growing and closed their stoma to conserve limited moisture.

Less obvious, but no less important, is how Plantra Tree Tubes enabled Babe to spray RoundUp in the tree rows to eliminate weed competition for light, water and nutrients. Tree Tubes make it easy to see the trees amidst the tall grass, and they protect the trees from herbicide spray. It's hard to say which factor - deer browse protection, moisture stress reduction, or reduced weed competition - contributed most to the amazing growth. In the end it doesn't matter which matters most, all that matters is that a planting project a dedicated landowner considered to be an expensive, frustrating failure is now a resounding success.

2) Rejuvenating a failed hedgerow planting, part 2. Based on the success of the 3/8 mile hedgerow section in 2008 we decided to rescue the remaining - much longer - portion of hedgerow in 2009, which two important changes.

First, we used 5 foot Plantra Tree Tubes instead of 4 foot tubes. In 2008 deer repeatedly browse trees as the emerged from the 4ft tubes. By applying Deer Guard Repellent to the emerging trees Babe was able to get the trees past the browse line. This a great solution for landowners who are limited by their initial planting budget to using shorter tree tubes than they would prefer (hey, a 3 or 4ft tubes a whole lot better than no tube!). Spraying emerging trees with Deer Guard will provide that last bit of protection to grow them past the browse line.

As effective as the 4ft tube/Deer Guard combination was in 2008, Babe wanted to avoid the added trips to the field to spray repellent in 2009, and chose to use 5ft tubes instead.

Second, we pruned all of the deer-browsed "bonsai" trees to a single stem before applying tree tubes. This adds time and labor at the beginning but it has two huge benefits: 1) All of the growth potential stored in those huge roots would be channeled into a single stem, resulting in faster height growth (getting the terminal shoot above the browse line more quickly), and 2) Produces trees with better form - fewer lateral branches and narrow branch crotch angles.

The results? In a word: Wow!
Joe took this photo (click to enlarge) on October 23. That's me standing next to a tree that was tubed on May 20, 2009 when it was no more than knee high. It is now very nearly 10 feet tall!

85% or more of the trees we tubed just this past May have emerged from 5ft tree tubes. What's the reason for the great results? Is it the fertile soil? Babe's soil could be charitably described as "gravelly loam." A less charitable description given by someone who has spent several days driving stakes into it is " rocks." So trust me, it's not the soil.

Is it the high rainfall? Ottertail County has been in a drought for several seasons. Was it the warm, sunny summer? I just came across this amazing fact on the East Ottertail SWCD web page:

Did You Know?

Perham had only one day 90 degrees or greater this summer.

Every night this summer had temps below 70 degrees.

I think that safely rules out unusually good growing conditions as the reason for the great growth. Again, it was a combination of browse protection, moisture stress reduction and the ability to do great weed control that unleashed the pent up growth potential in those root systems.

4) Planting white oak seedlings in forest openings to enhance hard mast production. Like many farms in the region, the hillier portions of the property were not cleared for farming, and the oaks (bur and red) that benefited from period prairie fires were allowed to grow. Over time, and in the absence (and active suppression of) fire, more shade tolerant species like basswood began to gain ascendancy in the woods. Basswood is a terrific tree, but it does not produce much mast for wildlife, and you generally don't want it to comprise a high percentage of your forest composition. So Babe worked with a local logger to harvest basswood trees from the woods. This has two benefits. First, the crowns of the basswood trees were competing with the crowns of the oaks for sunlight and growing space. Removal of the basswoods will give the existing oaks more room to grow, and they will dramatically increase acorn production in the coming years. Second, it created openings for planting new oaks - and Babe choose to plant white oak to provide a different (and sweeter) type of mast than his indigenous bur and red oaks provide - to get started.

Approximately 150 white oaks were planted, each in a 5 foot Plantra O-style Vented Tree Tube. While the results are not as exciting as the crabapples or the hedgerows (no stories of 10 feet of growth in one year), the results were terrific. On our recent visit to the ranch we replaced the few oak seedlings that didn't survive with direct seeded acorns which will germinate next spring. We'll easily see the first of the oaks emerge from their 5ft tree tubes next summer, and growth will be enhanced by further clearing of brush and overstory trees that are shading our seedlings.

All in all, another fantastic year at Babe Winkelman's ranch. And the best part is knowing that these are the kind of results our customers are seeing across the country.

Urban Forests from Tree Tubes

(Spoiler: Don't anyone ever tell me again that growing great trees in the urban environment won't work with tree tubes! It works and it works great)

Back in the early 90s we were experimenting with planting seedling trees in all sorts of locations using a tree tube to nurture and protect tender seedlings. I will be covering more examples in the weeks to come.

Some applications we just "knew" were doomed. One was a planting of native trees at Central High School in Saint Paul, Minnesota. The school has a long history. Famous grads include Charles Schutz of Peanuts fame and David Winfield the Hall of Fame ball player.

Some thought the planting would be a "feel good" exercise, but obviously the tree tubes would get run over by the kids. Here is what our experiment looks like today. Up against the build is an oak grove. The trees are absolutely fantastic. The trunks are thick and straight and tapered. These trees have not had any special care.

Grass grows up to the base of the tree. There is no mulch. No bark. No chips. No mats. I wish there were, but there is not.

Why plant bur oak in the city? My home in Saint Paul is not too far from here. There is a wild bur oak in my back yard I date to around 1850. In 1981 we removed a 114 year old limb that was ten feet up. These old (young by bur oak standards) trees are all over St. Paul.

Before the streets were laid out I think St. Paul was more or less a bur oak savannah. I love these old bur oaks. They survived and may have been aided by the brush fires that hit the area after all the trees were cut to support Fort Snelling. The white tail deer range was south of here when these trees were seedlings, so unlike modern oaks deer browse was not a problem.

The St. Paul bur oaks survived development. Five lived on our block when we moved here in 1981. Four remain. The largest and nicest was cut down because it had been defoliated once and the owners mistakenly thought it was dead. Bur oak is tough and a healthy tree can survive several defoliations.

Lets take a closer look at the CHS bur oak. Wow. Those trees look terrific. Beautiful trunks. Straight trunks. Yes, bur oak has a few epicormic branches, but that is normal.

If you look at the base of the tree on the left, you will see the remains of an old style Tubex treeshelter.

These tubes were left in place for at least seven years and maybe more. I'll try to find out how long. By the way, while we want you to leave the tubes on for protection as long as ten years, you should remove the tube before the trunk swells to fill and crack the tube.

I repeat, don't ever tell me tree tubes won't work in the urban forest. Tree tubes work and provide an incredible value.

The usual knock is vandalism. Look at the pictures above. If seedlings in tree tubes survive and thrive at my local high school, where won't they work? Vandalism is a fact of life, so would you rather lose a $200 B&B or a $20 seedling and tube? Your choice.

The other objection is visual impact. Plant a quality seedling in a Plantra four foot vented tree tube surrounded by mulch and you will have eye level foliage in 2-3 months. If you can delay gratification to the end of the summer, we can establish trees at 1/10th the cost of B&B.

So don't tell me it won't work and don't tell me it doesn't make sense.

America is under-planted and with emerging pathogens such as emerald ash borer getting more under-planted everyday. Plantra tree tubes will get the job done fast and at the lowest cost.

Let's start planting seedlings in our cities.

Chris Siems on Minnesota Bound with Ron Schara

Last Sunday was Chris Siems first of three one minute talks on Plantra Tree Tubes. This episode focused on the most economical method for replacing trees lost to Emerald Ash Borer. Hit the link and scroll down to the June 12, 2009 episode. Watch the whole show or let it load and jump ahead to the 9:30 minuute mark and enjoy.

Babe Winkelman likes Plantra Tree Tubes

Babe is developing a wildlife paradise in NW Minnesota. Unfortunately, the wildlife do not always cooperate. In addition to television, Babe also write a newspaper column. Here is a quote from a recent column:

After planting trees in protective Plantra tubes, I was absolutely amazed by the growth rate of the new seedlings. In one growing season they surpassed the height and girth of trees that I had planted years before without tubes.

To read the whole article go here. Scroll down on the homepage of plantra.com for a video link of babe describing his experience with Plantra Tree Tubes.

(Babe Winkelman is a nationally known outdoorsman who has taught people to fish and hunt for nearly 30 years. Watch his award-winning "Good Fishing" and "Outdoor Secrets" television shows on Versus Network, Fox Sports, Wild TV and many local networks. Visit www.winkelman.com for air times where you live.)

Dead bluebirds in shelters.

The other day the following email crossed my screen.

Folks,

Today(Th., 06/25/'09), I found another dead bluebird in one of our cone shelters at Raystown. It must have died a horrible death.

The Raystown folk are looking at getting mesh covers for the cone shelters. This is dead bluebird#02 and other bluebirds have been rescued out of the cone shelters. I encourage everyone to keep their shelters wide and I discourage the use of cone shelters without mesh covers. For some reason, bluebirds like to go down into the cone shelters. They don't realize the peril.

--Rick Entrekin
Huntingdon, PA.

Plantra responded with the following offer.

Plantra will supply free nets to anyone who requests them for any brand of tube. This is an important topic.

Yes, this is an important topic and I want fill in some history, offer some alternative solutions and ask for any ideas others might have for ways to keep bluebirds out of tree tubes without interfering with tree growth.


At the risk of giving away the ending, we are now recommending installing Plantra tree tubes with stakes on the inside so the birds just walk out.

In 1989, we had the first reports of bluebirds in tubes. (I co-founded Treessentials. We sold Tubex brand.) Other species also end up in tree tubes, but bluebirds do so more than others and since bluebirds suffered significant population loss, losing a single bird is a tragedy to avoid.

The first place we went looking for help was the foreign manufacturer. Initially, they denied experiencing any problems in the UK and treated us as though we were over-reacting. They were no help at first. Later, we learned they knew of the problem. Even The Royal Society for Protection of Birds knew.

Much to my surprise there was the equivalent of a gentleman’s agreement to ignore bird death in tubes. They suppressed the problem by reasoning the tree tubes were creating needed habitat for birds to use for centuries to come. The sacrifice of a few birds was a price worth paying.

I believe they were afraid that if the public knew, there would be an outcry against tubes and tree tubes were the only effective method of ensuring the establishment of young trees in the English forest. Believe it or not, in the UK over half of all broadleaved oaks and other hardwoods are planted with four or five foot tree tubes. The reason is that they do not tolerate planting failure. They expect every tree they plant to live and provide the protection required to get the job done. Why would anyone do any less? Tubex tubes sold in America were the first to supply a free net with every tube 4 feet and over. That policy continues to this day.

From a strictly biological perspective, I cannot argue with the logic of ‘sacrificing’ a few birds for the long-term benefit of the entire bird population, but we will never be satisfied with that solution.

Once it became obvious this was a serious problem and we were not going to get help from overseas, we had to find our own solution. With great trepidation, I called Sadie Dorber who was then president of the North American Blue Bird Society (NABS). Sadie listened carefully as I described how we introduced treeshelters to the US to protect oak seedlings from deer and generally ensure a future for oaks in America. She well understood the problems of plants and animals that evolved survival skills in habitat that no longer exists. She listened and to my surprise was very understanding. Sadie agreed there was a serious problem and offered her help. Bluebirds were dying needlessly in tree tubes.

Sadie told me they had a similar problem with the ventstacks on tobacco drying sheds. The solution was a simple wire mesh over the opening. Sadie put us in touch with Jack Finch. Jack had started the non-profit corporation Homes for Bluebirds, Inc. to distribute bluebird boxes. Jack was known nationally and Dan Rather had recently profiled his efforts. Jack Finch was the “go to” guy for bluebird problems. He once built a pit under bluebird nesting boxes and filled it with snakes to develop methods to keep snakes out of the nest boxes he was producing.

We sent Jack some tree tubes. Chris Siems, one of my two partners at Plantra and the first employee of Treessentials remembers how Jack set up his test.

“He put a wood slat across the top of the tube to reduce the opening size and prevent accidental entry (falling in) by birds, then attached the tubes to stakes so the bottom of the tube was 2-3’ off the ground, and attached a collection bag to the bottom on the tubes. He monitored the tubes/bags hourly, and captured bluebirds in the bags – meaning that the birds had to be trying to get into the tubes rather than falling in.”

Based on Jack’s tests, we decided to exclude the birds. Flexible mesh tubes slipped over the top were the easiest solution. We began supplying a free flexible mesh with every tube four feet and taller. We have not had much trouble with shorter tubes. I am somewhat surprised by the incident mentioned in the email at the beginning since it was in a shorter conical tube. It is rare to hear of a bluebird in a shorter tube.

There are additional theories for why bluebirds enter tree tubes.

1. Jack Finch’s explanation is that bluebirds are cavity nesters and tubes are attractive cavities.
2. Some folks say bluebirds eat bugs and enter the tube in pursuit of dinner.
3. I think some bluebirds actually fall into the tubes

Elements of all three might be true. Let us explore each reason

1. Bluebirds are cavity nesters and tree tube openings trigger an instinct to explore cavities even though the cavity faces the sky.

This seems odd in the sense that we expect a nesting cavity opening to be perpendicular to the ground, not open to the sky and rain the way a tree tube does. The instinct to explore cavities probably does not have an orientation requirement since tree cavities facing the sky can be quite spacious and provide adequate cover.

To my surprise, the NABS FAQ page has an entry near the bottom about open top nesting boxes. This style is discouraged because the nestlings get wet and die of hypothermia. The important point here is that the bluebirds nested in a box with a top open to the elements. That fact strongly supports Mr. Finch’s explanation the birds are looking for a nesting site when entering vent pipes and tree tubes. Even if unwise, cavities open to the sky are acceptable to the bird.

It could be that the ideal nest height triggers the instinct to explore a cavity. NABS says bluebirds will tolerate a nest as low as three feet, but prefer 4 or 5 feet. The bluebirdsforever website says: “The bottom of the nest box should be at least 3 feet above ground. Ideally, it should be mounted 4 to 5 feet above ground.” The reason given is that anything lower is more susceptible to predators. This strongly parallels our experience with tree tubes. Dead bluebirds are found in 4 and 5-foot tall tree tubes and rarely 3 foot. In over twenty years, I do not recall a single instance of a bluebird in a tube shorter than 3 feet.

Jack Finch’s explanation of birds looking for nesting sites probably covers the vast majority of cases. There are two other possibilities often put forth that may explain some cases.
2. Bluebirds eat bugs and enter the tube in pursuit of dinner.

According to http://www.wild-bird-watching.com/Blue_Birds.html insects make up 80% of the bluebird diet during spring and summer. A University of Michigan site states: Eastern bluebirds eat a variety of foods depending on the season. In summer months, eastern bluebirds consume mostly beetles (order Coleoptera), crickets, caterpillars, grasshoppers, and other insects. These are exactly the sort of insects found crawling on a leaf in a tree tube.

Given the obvious fact that bluebirds have no fear of entering a tree tube, it seems plausible a bluebird would drop into a tube to grab a beetle.

3. Bluebirds fall into the tubes



It is hard to imagine a bird falling into a tube. Still, we have all seen wildlife videos of botched landings by birds. (Click the link to the left and watch the video if you think birds always land perfectly) The tree tube in a field is a suitable perching structure and thereby creates bluebird habitat. The tree tubes become convenient perches from which to pursue flying insects or swoop down to the ground and grab a grasshopper. The hunting bird takes off and lands hundreds of times in a day. Not all landings are perfect and some tree tube designs make landing riskier.

The bluebird has three toes forward and one toe back somewhat like a thumb. Think of the rear toe as analogous to the tailhook on a jet landing on an aircraft carrier. If the tailhook misses the arresting wire, the plane hurtles forward and must take off or fall into the sea. Perching birds evolved to land on round twiggy branches covered with soft bark. The classic Tubex tube has a hard surface with a flair curved like a funnel into the tube.

When landing on a flared hard plastic rim the three forward toes have nothing to grab and can slide forward. To land successfully the rear-facing toe must catch the edge of the hard rim flare. If the single rear toe slips, the downward momentum of the bird will pitch it head first into the tube. Once in the tube it cannot open its wings to fly out and it cannot walk up the smooth inside.

This happened very quickly, but I remember standing in a field and saw a bluebird land on the tube rim and pitch forward into the tube. At least that is what I thought I saw. In retrospect, I might have been witnessing a nest search, a bug pursuit or a botched landing. Whatever I saw we have to keep the birds out of the tubes.

Solutions
Soft un-flared rim
Plantra tubes are made with soft low density polyethylene (LDPE). Since it is soft, it does not abrade tree bark. The Plantra tree tube does not need a bird sucking flare in the rim. You can bend or roll up an LDPE tube without damage. The softer more flexible rim might allow the claws a better and safer grip. The nested style tubes are made with a similar but hard plastic called polypropylene (PP). PP tubes resist bending and turn white if forced to bend. I think eliminating the hard curved rim helps, but it is not the complete answer. Some customers report fewer bird problems with Plantra tubes, but birds still enter our tubes. Eliminating the flare is not a complete solution.

Pinch the top mostly closed


Inch and a half entrance holes are recommended by NABS for eastern bluebird nesting boxes. That means the opening at the top should be smaller than 1.5 inches to exclude bluebirds.

This should only be attempted with a ventilated tree tube. Without ventilation, the unchecked photosynthesis in a tree tube depletes CO2 below the level photosynthesis needs to keep growing. Also without ventilation, moisture levels in the tube reach levels that cause fungal problems in some plants.

There are some other potential benefits of this approach. Birds do what birds do. We have seen cases where a tube becomes an extremely popular perch and the plant and tube become encrusted in feces. Any fertilization effect is lost if the plant becomes coated. The small opening should limit the amount of feces deposited in a tube.

Additionally, this configuration may produce a straighter stem. The apical meristem or terminal bud seeks blue light. For this reason, we make the sidewalls red to suppress branching in the tube and channel growth toward the blue light that naturally propagates down the tube from the strongly blue middle of the sky. The reduced opening at the top will create a smaller and more focused source of blue light for the terminal bud to aim for. I am speculating here, but that might create a straighter stem.



Put the stake on the inside of the tube.

Sadly, we find many growers do not use the mesh. Recently we have been working on another approach to prevent bluebird death. There is a video on youtube of birds in the UK nesting in a tree tube and walking up and out at will because the tree has emerged. Birds know how to walk up a tree stem. We always knew the problem went away once the tree emerged. This led to an obvious idea. Put the stake on the inside and the birds can walk out. So far, this seems to be working.

Traditionally, we have recommended putting the stake on the outside to maximize the available volume for leaf expansion. We feel if the stake is not overly large, putting the stake on the inside is a great idea.

There are several other benefits. If the stake is on the inside:
1. A buck will not rub the stake with his antlers.
2. The bird can walk up and out on the stake
3. The tube is more wind stable and has a reduced profile in the wind.
4. Rodents cannot use the stake to climb up to the tie hole and gain entrance.


If you have any other ideas, please send them to me at joelais@plantra.com and we will share them.

Again, If you need net we would be happy to supply it free of charge, but consider putting the stake on the inside.

It's the Carbon Stupid!

Question: “Interesting, you make and sell tree tubes. So what does a Tree Tube do?”

That is a stressful question at a party. Spouses of those of us in the tree tube industry get a look of alarm when we are asked the simple and innocent question, “What does a tree tube do?” The reason is that a tree tube seemingly does many things and there is no obvious end to the monologue. Where do we begin? Here is a partial list:

A Tree tube:

1. Is used on tree seedlings, acorns, nuts, tissue culture plantlets, grafted grape vines, and etc.

2. Protects the plant from deer, rabbits and other animals

3. Shields from herbicide spray

4. Blocks the wind

5. Conserves moisture

6. Trains the plant to a single

7. Modifies the quality, quantity and wavelength composition of the light hitting the seedling

8. Has photomorphogenic effects

9. Is not a season extender

10. Affects CO2 uptake

11. Protects against mechanical damage

12. Makes it possible to find a plant in the forest to take care of it

13. Works best with small plants

14. Prevents side branching

15. Saves training labor

16. Is made of translucent polyolefin

17. Is tubular

18. Must be the equivalent of 3.5 inch OD in cross-section

19. Prevent seasonal buck rub

20. Discourages rodents

21. Ad infinitum…

I could go on indefinitely.

For over twenty years, my colleagues and I have searched for understanding of what it is a treeshelter or tree tube does to makes trees grow so magnificently. The answer is complex and involves a great deal of plant physiology. What is the simplest way to express what a tree tube does? Around 1pm on Friday afternoon (19 June 2009), it dawned on me. It is possible in three or four words to express the purpose and function of a tree tube. A tree tube does Carbon Acquisition and Retention (CARe) CARe is all a tree tube does. Plantra Tree Tubes CARe!

Everything about a tube flows from these concepts. So here is the answer I have been looking for – with some attempts at developing a useful acronym.

Answer: A tree tube is a Carbon Acquisition and Retention Device (CARD for short) Acronyms help us hold and retrieve knowledge. CARD is not a helpful acronym for what a tree tube does. A better acronym would spell a metaphor. Hmm… CARE or CARe meets that test. So my answer could be “A tree tube is for Carbon Acquisition and Retention (CARe).” Just thought of a third acronym - metaphor. The answer could also be, “The purpose of a tree tube is Acquisition and Retention of Carbon (ARC)” I know Noah’s ark has a “K” and not a “C”, but it is highly suggestive of the notion of saving a species. The Plantra Tree ARC has a ring to it!

The short story is that a Plantra Tree Tube does two things. First, it helps the plant acquire more carbon than it would without the tube and then the tube helps the plant retain the carbon by preventing browsing animals from removing carbon in the form of leaves, buds and twigs.

CARBON ACQUISITION

Since water is most often used as the electron donor in oxygenic photosynthesis, the equation for this process is:

CO₂ + 2 H₂O + photons → (CH₂O)_n + H₂O + O₂

carbon dioxide + water + light energy → carbohydrate + oxygen + water

Every fan of science fiction has heard the expression that Earth based life forms – plants and animals – are carbon based. Life on Earth is fueled and made possible by Chlorophyll in leaves. Chlorophyll takes energy from sunlight to chemically convert water and carbon dioxide into sugar (carbohydrate), water and oxygen. Sugar is the fuel of life for both plants and animals. Animals consume plants to get sugar. Oxygen is consumed to “burn” the sugar fuel. When animals release the energy in the plant sugar, water and carbon dioxide are the byproducts. Therefore, animals produce the CO₂ & H₂O that plants consume to produce sugar and O₂ that animals consume in a never-ending cycle. It is all about moving the carbon from plant to animal and back to the plant.

So exactly how does a grow tube help the leaf take in more CO2 than an unaided plant? The carbon used in photosynthesis must enter the leaf through open stoma or stomata. The stoma is a pore in the leaf that opens and closes with the action of two guard cells. The problem is that water vapor escapes out the stoma when open (so does O₂, but that is not a problem). To conserve water the stoma only open when conditions are right for photosynthesis and it is not too dry or windy. If it is too dry or too windy, the loss of water is too great for the plant to remain turgid (not wilted) and the stoma close the guard cells. Closed stoma means no CO₂ and no CO₂ means no photosynthesis. The microenvironment in a tube is humid and still – no wind. There is little evaporative demand in the tube, so there is little loss of water when the stomas are open. Therefore, the stoma stays open continuously. (Bergez Dupraz 1997) There is no interruption in the supply of carbon (CO2) unless the plant depletes the CO2 in the tube. That will happen in an unvented tube on a sunny day that is otherwise ideal for photosynthesis. Without venting the CO2 level in the tube drop below a level that sustains photosynthesis and the plant goes into photorespiration and starts giving off CO2. Venting replenishes the CO₂ supply available to the leaf.

It is only a slight exaggeration to say that life on earth is about move carbon into plants, then animals and back. Plantra Tree Tubes move carbon.

CARBON RETENTION

This is the easy part. Plantra Tree Tubes prevent browsing up to the height of the tree. The tube is a visual and physical barrier. The animals can’t see the plant. The animals can’t get to the plant.