In polymer chemistry, polymerization is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many forms of polymerization and different systems exist to categorize them.
The thistle caterpillar is the larval stage of the painted lady butterfly. The adult insect migrates into Iowa each year from Texas and Mexico. Eggs are laid on both thistle and soybeans. The caterpillar is easily identified by the spines that resemble Christmas trees that have lost all their needles.
Canada thistle can be killed with either Roundup or 2,4-D weed killers. These weed killers will kill back the leaves on the plant and will kill back some of the root system. The best time to apply these weed killers is on sunny days when the temperatures are between 65 and 85 degrees F. (18-29 C.).hese weed killers will kill back the leaves on the plant and will kill back some of the root system. The best time to apply these weed killers is on sunny days when the temperatures are between 65 and 85 degrees F. (18-29 C.).