The purpose of this paper is to give growers and advisors the necessary information on the common weed issues in strawberry. The section contains general information on the effects of weeds on the levels of strawberry production, as well as options for combating specific pests. The report also uses data from a survey to approximate the scale of the problem in regards to what portion of farmers are affected by it.
Unlike diseases and harmful insects, weeds usually do not harm crops directly; however, it is well known that they can severely affect the growth rate and the resulting output of strawberries. This occurs because the soil contains a limited amount of nutrients, and the plants have to compete for the available resources. In addition, weeds can have better-developed root systems and draw more minerals from the ground than strawberries, further impeding their growth.
As stated in the task description, weeds tend to cause many issues, and it is challenging to separate them and determine the exact correlations between each problem and the plant that causes it. Despite this, weeds are not to be ignored, as 31% of participating growers consider them to be the greatest threat to their crop, compared to 38% for diseases and 4% for insects (John Christman III and Samtani, 2019, p. 3). Fortunately, there is sufficient research covering the ways of managing weeds, although it must be noted that this paper will only be covering the most critical parts.
Some of the most prominent weeds in matted row agriculture include common vetch, curly dock, thistle, and dandelion. It is recommended to use from 0.33 to 0.67 pt. of clopyralid (Stinger 3 EC) per acre against these (Sikora et al., 2020, p. 56). The pesticide can be applied before or after the harvest, but not within 30 days of it. It should also not be used in combination with a surfactant or other pesticides to avoid crop injury. Finally, the pesticide may not be registered in every state.
A particularly difficult weed to control is henbit, or Lamium amplexicaule, which affects both plasticulture and matted row strawberry fields, and can be found in row middles and planting holes. It can be eradicated by using 3 oz. of flumioxazin per acre, or 4 to 8 oz. of sulfentrazone per acre for plasticulture, and varying amounts of terbacil for matted row plantations (Sikora et al., 2020). However, unlike the previously mentioned weeds, pesticides for henbit must be applied before it emerges, and before strawberry is planted. If anticipating the appearance of henbit is not feasible, it can be removed by hand when it is grown. The plant’s appearance is characterized by square stems, circular or heart-shaped leaves located opposite to each other, and are covered with thin hairs on the upper surface. Henbit is similar in appearance to purple deadnettle, but they can be differentiated by comparing their leaf position. While purple deadnettle always has leaves that grow on petioles, henbits higher leaves are attached directly to the stem.
Cutleaf and evening primrose are examples of other weeds that need to be treated in advance. Researchers recommend using 3 oz. of flumioxazin per acre to combat these in plasticulture environments (Sikora et al., 2020, p. 50). The pesticides should be applied “at least 30 days before transplanting,” and before the plastic mulch has been laid (Sikora et al., 2020, p. 50). These weeds a slightly easier to combat then henbit, as they require a pesticide that is used in numerous other cases.
Reference List
- John Christman III and Samtani, J. B. (2019) A Survey of Strawberry Production Practices in Virginia.
- Sikora, E. et al. (2020) 2020 Southeast Regional Strawberry Integrated Pest Management Guide For Plasticulture Production.