Full TGIF Record # 115507
Item 1 of 1
Web URL(s):http://www.jstor.org/stable/2640977
    Last checked: 03/09/2016
    Requires: PDF Reader
    Access conditions: Item is within a limited-access website
Author(s):Garrett, Karen A.; Dixon, Philip M.
Author Affiliation:Garrett: Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon Garrett and Dixon: Savannah River Ecology Laboratory, University of Georgia, Aiken, South Carolina
Title:When does the spatial pattern of weeds matter? Predictions from neighborhood models
Source:Ecological Applications: A publication of the Ecological Society of America. Vol. 8, No. 4, November 1998, p. 1250-1259.
Publishing Information:Washington, DC: Ecological Society of America
# of Pages:10
Keywords:TIC Keywords: Competition; Spatial equilibrium analysis; Weed control; Weed density; Weed competition; Postemergence weed control; Models
Abstract/Contents:"Good management models for postemergence weed control require good estimates of which weed density produces an economic threshold yield. Because intraweed competition increases if weeds are aggregated, weed spatial pattern may be an important factor for inclusion in management models. Mathematical models of weed-crop competition have demonstrated that this may be the case, but the small number of field studies examining the effect of weed spatial pattern have given variable results. These studies have used sampling units at arbitrary spatial scales for determining the level of aggregation in weed counts. We suggest that the neighborhood size for weed-crop competition is a natural scale for considering spatial pattern. We modeled crop yield resulting from weed competition as a function of the economic threshold, the level of competition within the neighborhood, neighborhood size, and the type and scale of weed pattern. From the model results, we predicted which weed traits would produce large shifts in threshold weed density as weed spatial pattern varies. For these weed species, consideration of spatial pattern in weed management models is predicted to be important. The systems most sensitive to weed spatial pattern are those with low economic thresholds, less competitive weeds, smaller neighborhoods, and aggregation at the scale of the neighborhood.
Language:English
References:34
Note:Figures
Tables
Graphs
Includes Appendices, "The distribution of N under aggregation", p. 1259 and "Form of yield expectation for evaluation", p. 1259
ASA/CSSA/SSSA Citation (Crop Science-Like - may be incomplete):
Garrett, K. A., and P. M. Dixon. 1998. When does the spatial pattern of weeds matter? Predictions from neighborhood models. Ecol. Appl. 8(4):p. 1250-1259.
Fastlink to access this record outside TGIF: https://tic.msu.edu/tgif/flink?recno=115507
If there are problems with this record, send us feedback about record 115507.
Choices for finding the above item:
Web URL(s):
http://www.jstor.org/stable/2640977
    Last checked: 03/09/2016
    Requires: PDF Reader
    Access conditions: Item is within a limited-access website
Find Item @ MSU
MSU catalog number: QH 540 .E273
Find from within TIC:
   Digitally in TIC by record number.
Request through your local library's inter-library loan service (bring or send a copy of this TGIF record)