I don’t yet have the answer for why, in the woods, a number of tulip poplar trees have multiple trunks from the same base.
this tulip poplar has 4 trunks originating from the same base assessorized with python like vines
But the really unusual feature is how the base of the tree appears hollowed out.
hollowed out tulip poplar base
My current theory is that the tulip poplar grew up alongside the stump of a tree and then it sent out adventitious roots around the stump to mine the ingredients in the stump and when this was done and the stump had disappeared, it was left with a hollow base.
Here is another example of a hollowed out base.
another, larger example of a hollowed out base of a tulip poplar tree
But this may not be the reason at all – tulip poplars may have a predeliction for spreading their base out. Here is an unusual example.
unusual tulip poplar configuration
This tulip poplar leans over to the left and then grow upright. Usually this occurs when a tree is knocked sideways but there is no indication this tree was knocked sideways. Its trunk appears well planted upright in the ground. But then you notice that skeletal offshoot on the left – is that a trunk or a branch?
I really am not into cutting down trees gratuitously, especially not an oak tree, which is one of my favorite trees. When I made a road through the woods I selected a path which would require the fewest and smallest trees to be removed. But this week I needed wood posts. I did not wish to purchase the treated 4″ by 4″ posts because they are loaded with preservatives which will leach and be absorbed by the roots of my fruit trees, vines etc. Composite posts deform and are expensive. Even cedar posts rot over time. I concluded oak posts should hold their ground for several years, which is all I need at this time. But which oak tree to cut. Unusually, several oak trees have two trunks from the same base. Eventually the tree may split. It seems to incur little sacrifice to cut one of the trunks, the one which appears less vibrant. Then the root structure can feed the surviving trunk which will put out branches on the side where the other trunk stood.
twin trunked oak tree with left trunk removed at point where trunks met
It was quick work to cut down the one trunk and then slice it to leave a main trunk and six 8 foot length future posts. Plus the branches will dry and provide good firewood. The main trunk is too large for a post and I ordered shitake inseminated dowel plugs so I can have shitake mushroom logs. I have been very successful with shitake growing from oak logs. Some of the posts will be used to carry the trellis for my kiwi vines which I recently planted.
products from the oak tree – the trunk on the right will make shitake mushrooms, the 6 8′ posts will be used for trellises and the branches on the left cannibalized for firewood
And there is always a use for oak posts. My first beehive is well protected from winter winds but my second beehive needed protection. With my clam posthole digger I dug 3 2 foot holes and grounded 3 small diameter oak posts to which I attached a surplus window for west wind protection yet still providing setting sun exposure, and a primed plywood rectangle for north wind protection. My woods provide a windbreak to the east and I leave the south side open for the south facing entrance and because winds from the south are less common.
#2 beehive with west facing window and north facing plywood protection from winterly winds held in place by oak tree mini posts#2 beehive seen from east side, the three small diameter oak tree posts sunk 2 ft into the ground are clearly visible. also a strap to protect against upheaval from nocturnal visitors
I happened to notice the growth rings on the stump of the oak tree and this got me thinking as to why there are growth rings. I know about heartwood and sapwood – the heartwood which is at the center of the trunk is darker in color (from accumulation of compounds), provides structural support and no longer transports water and the lighter colored sapwood conducts water.
heartwood, sapwood and growth rings on trunk of oak tree. I must still saw the face smooth and at an angle to shed rain
But what causes the growth rings which are the alternating bands of light wood and dark wood. The light ring is produced by large thin-walled cells and the dark ring by small, thick-walled cells. The large cells are formed during the rainy season when the cells grow and the small cells during the period of dormancy or no growth. Dormancy occurs during the winter in cold climates and during the dry season in tropical climates. I suppose if it rained evenly throughout the year you would not get growth rings?
Yesterday, while walking through the woods, I noticed a very large oak tree leaf. Automatically, I looked up and around for the parent and saw just large pines and then, on the side, a smallish 14 ft oak tree. Could this small tree have produced such a large leaf, I wondered. It still retained some leaves and indeed they were very large.
small oak tree surrounded by much bigger pine and poplar trees
Now I know that oak trees will wait patiently in shrub form for an opening in the canopy above and then they spring to life. I have found 1ft high oak trees with 4 ft tap roots and know that a shrub like tree can be many years old. So to return to the riddle I hypothesized that the leaf size depends on the age of the tree and this smallish tree could be many years old. But that doesn’t work since a large nearby oak tree which I know is very old, has smallish leaves. And then, this morning, as I worked my way through my biology textbook, it fortuitously provided the answer.
a big leaf from a small oak tree – measures a foot in length
Some variation within a species is due to genetic diversity within individuals but some is due to response to the environment and this is called “phenotypic plasticity” meaning that the plant (its roots, shoots or leaves) are plastic or changeable depending on environmental conditions. The textbook (Biological Science by Scott Freeman 3rd edition page 798) states that oak leaves are a prominent example of phenotypic plasticity. Shade leaves (grow in the shade) are big and sun leaves are small. Shade leaves provide a large surface in order to absorb as much sunlight as possible. So that’s the reason why the small oak tree has big oak leaves compared with high standing oak trees which have direct access to the sunlight.
But then, the question could be asked, if absorbing sunlight is the priority why shouldn’t a big oak tree also grow big leaves? Leaves lose water (transpiration) and the more exposure to the sun the more water loss. In the shade however, humidity is higher and water loss is less so the large oak tree leaf in the shade can capture more light with minimum loss of water.
If we accept that the living world around us did not just happen, but is the result of millions of years of adaptation and improvement the question rises for me – why do so many insects (and frogs etc.) go through metamorphosis? I am referring to whole-change or complete metamorphosis where the juvenile form (called a larva) looks very different from the adult form. Think of butterfly and moth caterpillars (larvae) which change into flying adults. Or mosquito larvae which live and feed in freshwater and then change into pesky annoying mosquitoes.
I am not thinking here of the social insects such as ants and bees which also have complete metamorphosis and live in colonies where they are fed and protected by the adults. I can understand that in a colony where everyone hangs out, it makes sense for the adults to take care of the kids and to groom them into community behavior and it is easier to feed and groom little dependent larvae.
But what purpose is served by having a caterpillar larva precede the dainty butterfly? After all, grasshoppers don’t have complete metamorphosis. Instead there is a juvenile looking grasshopper called a nymph (wingless and sexually immature) which grows to become an adult. Or the tadpole the frog?
tadpole in the pond in the woods, just emerged from frogspawn
I posted that I was reading up on biology and in addition to the $10 textbook I acquired, I recently purchased a competing version for $4 (cost 1 cent, postage $3.99) – Biological Science by Scott Freeman 2007 edition 1,300 pages which delves more into understanding the why’s of life around us.
The Freeman book offers two explanations for complete metamorphosis. First is feeding efficiency, in that the adults and larvae usually feed on different materials such as the butterfly larvae on my vegetables and the adult butterflies on nectar. So the kids are not competing with the adults for food, which improves the survival prospects of both adults and juveniles (the juveniles more than the adults). The second explanation for metamorphosis is based on specialization in feeding and mating. The juveniles are sexually immature meaning they cannot breed so they focus just on eating and since this is their specialty, they do so exceeding well. The priority of the adults is mating and procreation and indeed some adults do not eat at all as they dedicate their life to ensuring future life.
All attractive hypotheses for this phenomenon of metamorphosis, something I had noticed but not considered.
In a recent post I mentioned that mushroom production in my mushroom shelter has been poor due to inadequate watering. The system I installed had a 0.5″ diameter water pipe run from a nearby slightly higher rainwater collection tank to the ceiling of the mushroom shelter from which the water flowed via bubblers onto the spawn impregnated logs. Water flow was weak and the bubblers often clogged.
source of water for mushroom shelter is the elevated rainwater collection tank which collects from the north facing roof
I rectified this by replacing the 0.5″ diameter pipe with a 1″ pipe and by eliminating the bubblers and using adjustable .75″ pipes to torrent the water onto the logs. I do not have the dispersion I had with the bubblers but the flow is strong and there is no clogging – any debris is blown out.
rainwater from the storage tank directed by adjustable pipes to the mushroom logs (ignore the horizontal white pipe)
Another watering improvement I made is to collect rainwater from the roof of the mushroom shelter and direct it onto the logs. First step was to install a gutter.
gutter attached to catch rainwater from mushroom shelter roof with pronounced dip to the left to feed into 4″ elbow
The open lower end of the gutter feeds into a 90 degree 4″ elbow attached to a 10ft 4″ water pipe. I crumpled chicken netting into a ball and inserted it into the open end of the elbow to trap leaves and debris before they entered the water pipe.
gutter on mushroom shelter feeds into elbow with protective chicken wire
It was then a simple matter to lead the 4″ diameter 10ft pipe into the shelter, cap the far end, and secure it ensuring it dipped from the elbow end to the capped end. With a power drill I made holes staggered along the length of the pipe.
4″ diameter 10 ft water pipe in place with staggered holes to ensure good coverage of mushroom logs
The improvements should ensure more reliable mushroom production.
In my 9/21 post I described various tactics I am using to eradicate Bermuda grass organically and how I covered an area with 6mm thick commercial grade black plastic. Bermuda grass likes heat and rather than try solarize it with clear plastic (and this would only have possibly worked if I had tried this before the onset of summer), I thought completely depriving it of light might be more effective.
Today, some 3 months later, I decided I needed some of the covered area to plant out my remaining garlic cloves. Also I was curious to see what effect the exclusion of light had on the bermuda grass.
Bermuda grass area covered with thick black plastic 3 months ago
I lifted some of the black plastic covering, forked up a chunk of soil and pulled on the Bermuda shoots. To my surprise they slipped easily out of the soil, much more easily that an adjacent area which I had just finished clearing. So I decided to look more closely and noticed that the fungi strands on the ground, which I associated with the wood chips I had dumped the previous year, were actually decomposing the roots on the Bermuda grass shoots. Without their roots, the Bermuda grass shoots slid easily out of the moist soil.
fungi from woodchips laid the previous year have invaded Bermuda grass roots
So the fungi attacked the roots. I am assuming this is decomposing (saprophytic) fungi (rather than parasitic) and they migrated from working on the wood chips.
another photo of the fungi decomposing the roots of the Bermuda grass
This could mean that either the Bermuda grass had died or had gone into a very deep withdrawal. Bermuda grass hibernates every winter – it turns white and to northern visitors looks as if it is dead. But in the spring the green shoots appear and, as the weather heats up, it comes vibrantly to life. But I have not seen fungus attack overwintering Bermuda, so it seems likely that the black plastic covering had a significant effect.
I shall leave some of the covering in place through spring and then see if the grass can rejuvenate itself, and if it doesn’t then this will be a viable non manual yet organic way to combat Bermuda grass – establish fungi, seclude the grass from light and let the fungi do their work.
In the meantime I shall continue clearing the now vulnerable Bermuda grass from more of the area so I can install garlic and several varieties of kale which should do well in the winter in this very sun exposed site.
