Palmer amaranth (Amaranthus palmeri), a member of the "pigweed" family, is one of the most troublesome weeds in many southern row crops. Seed can germinate all season and plants can grow to over 6 feet in height. Plants have either male flowers that shed pollen or female flowers that can produce up to 600,000 seed per plant. One Palmer amaranth per 30 foot of row can reduce cotton yield by 6 to 12%.

Palmer amaranth (Amaranthus palmeri), a member of the "pigweed" family, is one of the most troublesome weeds in many southern row crops. Seed can germinate all season and plants can grow to over 6 feet in height. Plants have either male flowers that shed pollen or female flowers that can produce up to 600,000 seed per plant. One Palmer amaranth per 30 foot of row can reduce cotton yield by 6 to 12%.

Invasive exotic species are plants that are not native to a given area and have the ability to out-compete indigenous plant species. Invasive exotics are often brought into their non-native surroundings by humans with good intentions.

For small fruit growers, weed management is one of the greatest challenges they will face to successfully grow these crops. Factors such as climate, new weed species, weed species shifts, and years of agricultural activity have come together to select for weed species that are aggressive and persistent. Without management, weeds compete with crops for light, nutrients, and water, resulting in reduced vegetative growth of the crop plant, poor fruit quality and lower yield. Stressed crops are also more susceptible to disease and insect infestations, while excessive weed growth itself creates higher humidity in the crop foliage, enhancing disease spread and inviting unwanted insects. Weed management principles for the perennial small fruit crops are similar, with the exception of strawberries in the annual system. Grapes, brambles, blueberries and matted row strawberries are considered permanent plantings in which weed management must be addressed throughout the life of the planting. When compared to annual crops, perennial culture is a greater challenge, as weeds need to be managed through all seasons and perennial weed species increase in numbers and diversity. Understanding seasonal weed thresholds, and integrating cultural and chemical management becomes even more important in the year-round culture.

This publication provides information on giant hogweed identification, including how to distinguish between look alike species, and what to do if you think you have found giant hogweed.

Grassy weeds in pastures and hayfields compete with desired forage species and reduce the productivity of forage systems. Lack of selective herbicides makes grassy weed species, such as Johnsongrass, Japanese stiltgrass, broomsedge, and foxtail species difficult to control. Proper soil fertility, grazing management, and correct timing and placement of herbicide application can effectively control these species.