Beneath the Ground

Much of the time when we think about planting trees, growing trees, and enjoying trees we think about what happens above the ground, and on the ground. But some trees and treelike plants, such as the Glauca Grass Tree, or xanthorrhoea glauca not only have soil and nutrition requirements, but also need special companion bacteria in the soil.


Grass Trees Are Not the Only Ones

Xanthorrhoea is a uniquely Australian monocot, which might allow people from the northern hemisphere to assume that such specific underground requirements are unique to such Australian grown vegetation, but that would simply not be true. Grass trees are not the only forest giants affected by what is going on around their roots.

Not only are nutrients and underground life important to help plants, they can also be detrimental. The kinds of underground life good for trees in one region might not be good for plants in another area. In most places, we think that earthworms are good for the soil. They eat up vegetative debris and poop out some of the richest soil available. They help aerate the soil and improve its permeability. Just a little farther down, we will look at how that just might not be good for native plants in some areas.

Speaking of permeability brings us to soil moisture. Most plants in desert areas are used to hot, dry weather. But what happens in cases of extreme drought? Both the Joshua Trees in the southwestern part of the United States, and the baobab trees Africa are slowly succumbing to prolonged drought and climate change, right along with some of the ponderosa pine and pinyon forests in the United States.


What Can You Do About Your Underground?

Human activity does affect trees and forests. There are several things that you can do, in general, and a few specific things in various locations.


General things to do to Protect Trees and Health of the Soil Under Them:

  • Check before you dig or plan construction. Everyone knows that before you start digging a foundation or creating a parking lot, it is a good idea to find out if there are utility lines or gas or water pipes, but what about special plants, soil types, animals or even insects? Maybe you cannot save everything and still reach industrial or commercial goals, but perhaps you can. Having a word with your local conservation or land management authorities is a good idea before even getting out a single spade.
  • Always buy your plants from licensed providers. Designer Trees is licensed to plant, sustainably harvest, transplant, and generally care for all sorts of rare trees and plants. If you check out website’s “about” page, you will see that Tony got his start by transplanting dracaena draco that were in danger of being cut down or otherwise destroyed to make way for construction. We think that is just amazingly cool.
  • Only wild harvest where you have permission, or you own the land. While not all private owners are aware of the value of their trees and other plants, many are. That beautiful tree that seems to just be standing out there alone and that is just beginning to bear seeds might actually be under close watch by an owner or by a park service. Even if you own the property, it is a good idea to ask local growers about the best way to transplant, cut pieces for grafting, or gather seeds. Good information helps preserve plants.
  • Use caution when introducing non-native species of anything. Even plants that are normally beneficial can become a problem. Nearly everyone loves olives and can agree that they are a good thing to have. But when they were planted in Australia, they have been found to like the climate almost a little too much and that they can crowd out native species. It is possible to have too much of a good thing, so be informed about plants such as olive trees, and know how to best manage them.


Specific Plant Surprises

  • Just a quick word about Glauca Grass Trees. These iconic Australian monocots are amazing treelike architectural plants for nearly anyone’s dry weather garden. But they are picking about their underground helper fungus. The good news is that the mycorrhiza starter is now available commercially, making it easy to keep it going. Folk wisdom says to add the starter to your soil, then to water it once a month with water to which brown sugar has been added.
  • Earthworms as the Bad Guy. It almost boggles the mind, especially if you’ve grown up thinking of earthworms as being your garden’s best friend. But don’t take these guys to Michigan or anywhere around the Great Lakes area in the United States. It seems that they’ve not been native since glacial times, and they can wreak quite a bit of ecological disaster. When earthworms are imported to a non-earthworm area (usually as fishing bait) they compete with the local underground life for vegetation. In some areas, their tunneling can weaken soil structures in a way that can loosen the earth around tree roots, making it easier for them to topple over. It just goes to show that a helper creature in the wrong place can become the Bad Guy.
  • Is It Climate Change? From Baobabs to Joshua Trees, we do not always know why certain trees are dying. We can make good guesses such as climate change, changes in grazing land, superhighways and more, but sometimes what we think is the cause of something is just a good guess. But if you needed a reason to purchase a Queensland Bottle Tree (brachychiton rupestris) instead of a boab (adansonia gregorii) then the puzzling slow loss of some of the earth’s biggest plants is a really good one. Besides, Queensland bottle trees are both beautiful and available.



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