Weeds and the soil environment - Ecological Management of Agricultural Weeds - page 256

In warm climates, and for crops that can emerge through dense residue,
trailing wheels that brush residue into the crop row behind the planter unit
would allow concentration of mulch in the zone that is most difficult to weed
mechanically.Athree-fold concentration of mulch over the row should be pos-
sible, and in many cases this would increase the mulch from an ineffective to
an effective rate.
Finally,better methods could be developed for moving crop residues on the
farm. Moving mulch materials is rarely cost-effective for producing field
crops, but may be practical for some horticultural crops. Some fruit and vege-
table growers have fields that are unsuited to intensive management of high-
value crops. These could be planted to forage species and mowed periodically
to provide material for soil improvement and weed suppression on the inten-
sively managed fields. Care would need to be practiced to prevent introduc-
tion of weed seeds with the mulch. However, few weeds of perennial forages
go to seed in late spring when the mulch would be most useful for production
of summer crops. The biggest hurdle to moving mulch is that machines cur-
rently available for spreading bulk materials are not well adapted to spreading
mulch between established plants.In some tropical regions,forest leaf litter is
moved to nearby fields (Wilken,1977),and simple human- or animal-powered
machines could greatly reduce the labor involved.Mechanical management of
mulch will likely be a fertile field for collaboration between farmers, agricul-
tural engineers, weed scientists, and ecologists in the coming years.
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