My intuition would be that a sharp dropoff of water demand in the surrounding soil, plus lots of rotting nodules, would result in a burst of growth for a tree in that situation.
I guess some demanding plants taking the place of those N-fixers would be important.
"the qualities of these bacteria, like the heat of the sun, electricity, or the qualities of metals, are part of the storehouse of knowledge of all men. They are manifestations of the laws of nature, free to all men and reserved exclusively to none." SCOTUS, Funk Bros. Seed Co. v. Kale Inoculant Co.
i have been using annual or small perennial nitrogen fixers around my dwarf fruit trees, like annual beans and peas and lupines...so phasing them out wouldn't really be much of a problem..for me. I have nitrogen fixing shrubs and trees all over the property but under the dwarf fruit trees decided that the annuals and lupines would make a better choice
Bloom where you are planted.
Nice. I'm also playing with sowing annuals around young trees and shrubs, so i don't have to cut grass all the time.
Is this already working for him, about trees not getting bigger? I think trees will just grow further. Maybe not so fast or what... Do you know what he is having in understory after removing n-fixers. Grasses?
In my experience, grasses under a fruit tree makes things really sucky for the fruit tree. But I suppose one could say that is part of the mission: grasses would take up the N.
I would think I would want the tree to always be growing and vibrant, so I would leave the n-fixer and keep grasses out. If the tree got too big to harvest, then whatever fell from the tree would be pig/chicken food.
Location: South Puget Sound, Salish Sea, Cascadia, North America
posted 9 years ago
I imagine that (particularly in the Bullock's climate) competition for water might also be an issue such that as the applecanopy begins to close, a woody competitor may not be as useful despite its nitrogen import. I wonder if stand density is part of the calculus.
Another factor may be where rapid growth can produce weak wood that cannot bear the weight of fruit in cultivated varieties.
Paul Cereghino- Stewardship Institute Maritime Temperate Coniferous Rainforest - Mild Wet Winter, Dry Summer
posted 9 years ago
Ironically, most methods I can think of to "take out" or "phase out" the n-fixers will end up leaving a lot of their nitrogen in the soil (which is usually what you want, but maybe not in this case?)
I guess this really would need to be a phasing out, where you gradually hack back the n-fixer as the tree it is near grows to the size you're wanting. I guess I just wanted to point out that most methods of removing or phasing out the tree are going to leave more available nitrogen in the soil than leaving it there.