Today we’ll look at a possible “element” for use in a Permaculture design. In this case, we want to emphasize how a “support species” is used to nurse a more important “production species” into better health and higher production. For our example, we’ll use the Empress Tree. This is sometimes called the Foxglove Tree, among other names. The scientific name is Paulownia Tomentosa.
I chose this tree, because of a conversation I had with my “plant identification” mentor. The backstory on this is that I am in the middle of doing a Permaculture design for a client. I visited the client’s property to walk with them as part of the design preparations. When I walk a property, I’m doing several things.
First, I’m looking at the slope and orientation with my own eyes. Second, I’m looking at the wildlife already there. I look at the plants to give me soil indicator information, and I look at signs of wildlife to give me indicators on what animals might be beneficial vs. what might be considered “pest” for the site. I try to catch things the client might not, such as noise sectors, and eyesore sectors. I look for how the water sits or flows. I take in a lot of information when I walk a property, and all of it is important for doing a “good” design, as opposed to an “okay” design.
On this particular property walk, we came across this tree. I’d never seen one before, and I had no idea what it was. It was near a stand of honey locusts, in an open field. The tree is deciduous, and all I could see on it were these nut like seed pods. They are shaped kind of like a green walnut (fleshy part outside the walnut shell) but smaller, and not fleshy. The size reminded me of pecans, but it definitely wasn’t a pecan tree. I pulled down a pod and peeled back a corner of the papery “shell” to find a nut like structure inside, which added to the confusion. Why was this confusing? Because the “nut” obviously was not the “seed.” It was packed with lots of tiny seeds with a white, feathery disk like structure around each seed. I was perplexed.
I tried to find what this might be on my own using google terms to describe what I found, but came up with no useful information.
Fast forward a week or three, and I finally ask my mentor if she knows what this could be. I sent her a picture of the seed pod partially opened with seeds inside, and her reply was priceless. I won’t give the exact phrasing, but she did not think highly of this tree. She did use the term “trash tree” at one point, and mentioned a popular synthetic pesticide product for the removal of said plant. I thanked her for the information (I now had a scientific name to look it up,) then went to work on researching it.
This tree (by reference definitions) is actually a very GOOD tree for Permaculture purposes. It would be used as a “nurse” tree, or a “support species” if the inherent properties I read about are correct.
A support species is often planted to provide for the needs of a production species. In a hypothetical design, we might have a species that doesn’t prefer direct sunlight (such as an understory tree like the paw paw.) This tree would want at least some shade during the heat of the day, especially when it is still quite young. We could plant a faster growing shade tree near it on the sun facing side. Ideally we would want to be able to cut this support tree back a bit in the cooler months, and also ideally, it would provide some fast decomposition to produce more soil at the base of the production tree. This is called a “chop and drop” system. Usually our support species are legumes, because we want to also place nitrogen into the soil, and every time we chop a nitrogen fixer, we force it to let go of some of its nitrogen to the soil.
The Empress Tree is “the fastest growing tree on the planet,” according to reference sources. It also has a high nitrogen content in its abundance of large leaves, which means when we chop it and drop it, we are not only adding carbon to the soil, but nitrogen rich material, as well. And some sources claim it is also a nitrogen fixer in the traditional sense. If this is true, then it should be dropping nitrogen nodules in the soil itself every time we cut it back some. Being a fast growing tree, the wood should be “soft” (even though it is a hard wood in the traditional sense, since it is deciduous.) Softer woods break down faster in most cases.
So what we have is a tree that grows faster than the shade loving plants, is high in nitrogen, coppices/pollards very well, breaks down into soil quickly, and is also shade intolerant itself.
Being shade intolerant means we can force it to die off once it has lost its use by planting another tree on ITS sun facing side to shade it out, then do our twilight years of chopping and dropping. Eventually due to heavy shade, it will stop sending up new trunks, and just die. The dead material will continue to feed the soil, and it will serve a support role its entire life cycle.
The leaves are great animal fodder, as well, which means it can be used for more than just supporting one element in the system. We can gather some of the leaves to supplement feed for our livestock.
Finally, the tree really is gorgeous during the flowering season. It would improve the view for some folks, which always helps when neighbors find our “jungle” of a food forest to be too “ugly” for the neighborhood.
Support species are put in to help nurse a young element into a stronger long term production element in a shorter amount of time. This tree shows its ability to perform this role quite admirably, if the sources are correct. It provides fast shade, nutrient from chop and drop, fodder for livestock, and a great view. It is also easy to control with the right conditions in play.
In the end, it didn’t tell me anything about the soil in the area I didn’t already know (from the nearby honey locusts.) It’s an indicator of poor soil, and its job as a pioneer plant is to fix the nutrient deficiency. The honey locusts were doing the same.
I gave my mentor some of this information, by the way. She said she had no idea “that monster” had so many good qualities. I’m grateful that she was able to help me discover this element and all its potential uses. It’s in my design element database now, for future efforts.