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Re: Soil management around trees
Vegetation control around trees is the single most important
factor. This has been proven to be true in countless
research trials and through decades of experience by tree
planters and landscapers. It outweighs fertility and irrigation.
Grasses and legumes alike will compete with young trees for
water and nutrients. Some herbaceous species exude
chemicals that inhibit growth of other nearby plants.
The effect is that young trees struggle to survive and those
that do are stunted in growth in comparison to trees which
have been maintained vegetation-free.
The survival phase lasts 3 years, but especially the
first growing season. The estabishment phase extends
to 5 years. Thereafter, landscape trees can compete with vegetation
adequately, but orchard trees will still need grass control.
Two recent studies on pecan tree establishment in Alabama
provide insights:
* A 5' radius from the trunk should be vegetation-free; thus,
a 10'x10' square area is needed
* Legumes, which can be so important in a mature orchard to
provide Nitrogen and provide habitat and food prey for
beneficial insects, should also be controlled around young
trees
* Disking as an alternative-to-herbicides method of weed control
was comparable to herbicide-treated plots when drip
irrigation was used. Yields were reduced by half when
irrigation was eliminated on disked plots in comparison
to herbicide-treated plots. Thus, tillage works when
irrigation is available but when trees are dry-farmed,
the no-till plots worked better. A mulch--a type of
no-till--should perform similar to herbicides, and that has
been the case in many studies.
Fabric mulch with water-absorbing gels:
A heavy-duty fabric weed mulch combined with hydrophyllic
polymers can provide a no-till, no-weed, no-irrigate mulch
system for upwards of 10 years. The cost of establishment
for the fabric pro-rated over 10 years is about $100 per acre.
This is well worth it when you consider the expense and labor
associated with non-chemical weed control; i.e., tractor cultivation,
hand hoeing, organic mulch costs, labor, headaches and worries, etc.
Sheet mulch:
A good layer of newspapers covered by straw, hay, or grass
to keep the paper from blowing away will provide an
effective sheet mulch of organic composition which will
harbor worms and microbes underneath, especially since the mulch
decomposes.
Follow-Ups:
References: