Some
might wonder why a Natural Gardener would use glyphosate salts, originally sold
under the brand name Roundup and now available in a host of cheaper generic
forms.
“Natural”
gardening is not “organic” gardening. We
aren’t concerned with not using artificial chemicals as much as we are with not
interfering with natural processes that maintain ecosystem health. An organic gardener may till the soil and
leave it naked; the natural gardener avoids tilling and keeps soil covered with
mulch. An organic gardener may use
“natural” plant-based pesticides like pyrethrins or nicotine that kill
indiscriminately; a natural gardener will use only pesticides that target a
single type of pest, preserving predators and keeping in mind the danger of
building resistance in the target.
Gardening
is mostly killing plants. Glyphosate is
a plant killer that is safe for people and most animal life; insects are in far
greater danger from the surfactant added to help it stick than from the active
ingredient. It is also less of a danger
to nearby plants than other herbicides, as it must be sprayed on a green
surface of a growing plant to have any effect on it. It does not penetrate brown bark. It does not travel through soil or persist
for long; it sticks to soil particles and is eaten by microbes in three days to
a week or so, depending on temperature.
If
a plant has a lot of food stored in its roots, glyphosate will not kill it with
a single spray; it takes two sprays in a growing season to kill blackberries
and dandelions. If a large bush or tree
catches a little spray on a branch, the branch may be affected but the rest may
not show any damage. Glyphosate damage
shows up in yellow new growth that is often dwarfed; it also cause “witch’s
broom” growth of twigs.
The
downside of glyphosate is that it is also a powerful fertilizer, being an amino
acid, glycene, with a phosphate group attached.
Animals kick that weird amino acid out of their bodies; plants try to
fit it into their proteins as they grow, and the proteins don’t work. Amino acids are full of nitrogen, so it
becomes high nitrogen and phosphate fertilizer as it breaks down. It should be used sparingly, but frequently
enough to prevent flowering and seeding.
If sprayed in flower, many weeds can ripen seeds before they die.
Unlike
chemical fertilizers and like organic fertilizers, it feeds soil microbes
first. Worms and pill bugs consume the
soil and dead plants to which the microbes are attached. Moles follow, eating the worms. Spraying a large area is like a dinner bell
to moles.
Pill bugs eat dead leaves and seedlings. When they are done eating and multiplying on
dead, enriched vegetation, they proceed to the only food available; your
seedlings. Until their population
crashes, it can be impossible to grow much of anything from seed in an area
treated with glyphosate and then mulched with compost, wood, and bark, which
pill bugs don’t eat. But they love
carrot seedlings; planting a lot of carrot seed can distract them from other
seedlings long enough for your preferred plants to grow out of danger.
Published
at AssociatedContent.com under The Natural Gardener #9.
I use very little glyphosate these days; the fertilizing effect is too powerful. But when a place is completely out of control, it can be used to gain the upper hand.
ReplyDeleteAlso, it is useless try to kill annuals in cool weather, as they immediately go to seed, no matter how young. One ends up with much the same seed load from a lot of little plants rather than fewer big ones that are far easier to pull. Plus, you've fertilized the next crop of weeds.