management conditions, such concerns appear to be
unfounded. Cutter and Garrett (1993) reported that
height, diameter and specific gravity were greater for
alley cropped walnut trees than for trees grown
under woodlot-like conditions. Furthermore, based
upon growth during the first 17 years, 50-60 year
veneer log rotations are projected for alley cropped
trees compared with a customary 80-100 years for
conventionally-grown trees.
Numerous economic assessments have been conducted
on agroforestry alley cropping with typical
internal rates of return ranging from 4 to 11% (Kurtz
et al., 1984). In general, returns tend to increase with
management complexity and site quality. Moreover,
tree species which yield especially high-value wood
products and fruit or other marketable products have
obvious advantages over low-value species which
produce only wood products. Assessments made of
alley cropping on marginal quality farm land have
shown that alley cropping produces land expectation
values comparable to those of traditional agricultural
systems (Lottes, 1985). Furthermore, the planting of
valuable hardwood species with nitrogen-fixing
woody and herbaceous types has been demonstrated
to be an economically viable alternative to conventional
row crops on these sites (Gordon and Dawson,
management conditions, such concerns appear to beunfounded. Cutter and Garrett (1993) reported thatheight, diameter and specific gravity were greater foralley cropped walnut trees than for trees grownunder woodlot-like conditions. Furthermore, basedupon growth during the first 17 years, 50-60 yearveneer log rotations are projected for alley croppedtrees compared with a customary 80-100 years forconventionally-grown trees.Numerous economic assessments have been conductedon agroforestry alley cropping with typicalinternal rates of return ranging from 4 to 11% (Kurtzet al., 1984). In general, returns tend to increase withmanagement complexity and site quality. Moreover,tree species which yield especially high-value woodproducts and fruit or other marketable products haveobvious advantages over low-value species whichproduce only wood products. Assessments made ofalley cropping on marginal quality farm land haveshown that alley cropping produces land expectationvalues comparable to those of traditional agriculturalsystems (Lottes, 1985). Furthermore, the planting ofvaluable hardwood species with nitrogen-fixingwoody and herbaceous types has been demonstratedto be an economically viable alternative to conventionalrow crops on these sites (Gordon and Dawson,
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