Weed infestation is a common problem in agriculture that adversely affects crop production. Given severe constraints on the budget of many landgrant universities due to the economic downturn, outreach services have taken a hit. To adapt to current economic climate without adversely affecting the quality of outreach program for weed management, we present a hierarchical system that uses image ca...

The ability to manage weed infestations in a spatially precise manner will rely on the availability of efficient methods of mapping weed distributions. We have conducted a study designed to compare four different ground based methods for collecting georeferenced information on sterile wild oat infestation in a winter barley crop. Sampling was done at harvest time (when wild oat panicles are mos...

June 23, 2000 Deciding whether a specific weed infestation is worth treating is usually based on a subjective evaluation of the potential impact of the infestation on crop yields. The two main criteria used are 1) the number of weeds present, and 2) the specific weeds present (foxtail, velvetleaf, etc.). Another factor that is just as important, if not more so, is the emergence date of the weed...

An important objective in weed management is the discrimination between grasses (monocots) and broad-leaved weeds (dicots), because these two weed groups can be appropriately controlled by specific herbicides. In fact, efficiency is higher if selective treatment is performed for each type of infestation instead of using a broadcast herbicide on the whole surface. This work proposes a strategy w...

Rubber tree production is reduced by weeds that compete for environmental resources; therefore, the timing and duration of weed control influences weed interference. The objectives of this study were to evaluate the growth of rubber tree (Hevea brasiliensis) plants, to determine the critical period for weed control, and to evaluate the growth recovery of rubber trees that coexisted with weeds f...

This paper analyses the potential and limitations of airborne remote sensing systems for detecting crop growth variability and weed infestation within paddocks at specified capture times. The detection of areas of crop growth variability can help farmers become aware of regions within their paddock where they may be experiencing above and below average yields due to changes in soil or managemen...

Weed emergence timing: a new tool for managing weeds in crop fi elds The success of integrated weed management relies on matching control strategies to the specifi c weed problem in a fi eld. Managers must know not only which weed species (and how many) are present in a fi eld; they also must understand the distribution and development stages of these weeds throughout the fi eld. Weed control r...