multivariate poisson hidden markov models for analysis of spatial ...

4.2.2.1 Effects on crop quality
Wild Buckwheat makes swathing and combining difficult. With 5 plants per square
metre, yield losses of 12% in Wheat can occur. With 30 plants per square metre, yield
losses can jump to 22%. Yield losses of up to 10-20% have been reported in Flax with
weed densities of 5-15 plants per square metre. The yield losses caused by this weed
can be highly variable, depending on whether the weed emerges before, with, or after
the crop.
4.2.3 Dandelion
Dandelions are present at all seasons of the year (perennials), and can be reproduced by
seed. They are almost stemless and have deep thickset taproots. The leaves are in a
rosette, 7.5-25 cm long and variable in shape (Figure 4.3). The flowers are bright yellow
and are produced on a hollow, upright stem that is 30-45 cm in height. The seeds are 3
mm long and attached to a hairy parachute.
4.2.3.1 Effects on crop quality
Dandelion usually has little effect on forage crop quality. Established Dandelion causes
yield losses in annual and winter annual crops and perennial forage seed crops.
Dandelions can shorten the productive life of perennial forage seed crops. Dandelions
also reduce productivity in pastures and hay crops.
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