Agriculture Reference
In-Depth Information
Steam Weeders
Steam weeders can be useful in an orchard floor management program.
Early steamer models were extremely expensive tractor-mounted units.
Pushcart models with handheld wands are now available in North America
for around $4,600 USD, compared with a comparable flame weeder for
around $300 or less. Steam weeders have promise for fruit growers, but their
high initial cost, slow speed of travel, and large propane requirements lim-
it their usefulness for many growers at this time. Expect improvements in
design that will lower equipment costs and make the devices more attractive
to fruit growers.
Infrared and steam weeders are less likely to cause unintended fires than
flame weeders, but they can still damage fruit trees if used incorrectly. Be
sure that the equipment's design fits your application.
Organic Herbicides
While conventional growers enjoy a wide range of herbicides registered for
fruit crops, organic fruit growers have very little to choose from. Worse, herb-
icides that are accepted by organic programs do not work very well for any-
thing but young seedlings. Herbicides can be effective for spot treatments
in an organic orchard. Five basic types of organic herbicides are available
to organic fruit growers: acetic acid (vinegar), citrus products, clove oil, corn
gluten, and herbicidal soaps. Except for corn gluten, all appear to be effective
against young seedlings, although none control established perennial weeds
well. Combining soap and citrus oil products may prove more effective than
either product alone.
Acetic Acid
Acetic acid can be used as an organic herbicide. Acetic acid is the active
component of vinegar, and it chemically burns delicate plant tissues. The
vinegar sold at grocery stores contains about 5 percent acetic acid; several
commercially available herbicides contain higher concentrations. In tests
conducted by Cornell University, household vinegar had some short-term
