Beet armyworms have not been found this week in scouting fields. Cotton boll weevil pheromone traps are averaging zero in 92% of fields and less than 1 in 8% of fields. No fields have required weevil treatments as of yet. Early season weed control continues in cotton and peanuts. Hot conditions have staved off any disease problems.IRRIGATION DECISIONS
It is important to have as much water stored as possible going into bloom period, during which the water use and plant sensitivity to stress reach their peak. I must temper my comments on irrigation with the fact that input costs (pumping costs) must be kept to a minimum and at the same time maximizing these inputs (irrigation water) when needed. We must maintain better than 65% square set going into bloom. If the plant is stressed sufficiently enough during squaring from not having moisture available square shed will occur. We must also consider that insects and the hot winds will take their unfair share of squares. Therefore, I would suggest no less than 1-1.5" of irrigation be applied within the next 5-10 days, if rain is not received. This will wet back the top 8-16 inches of the soil profile depending on soil type of course.

They are uniformly pale green with red-tipped antennae; late instars have four conspicuous black spots on the thorax and one large black spot near the base of the abdomen. The nymph's wings are not developed, but nymphs can move rapidly and are difficult to detect in cotton foliage. Small nymphs may be confused with aphids, cotton fleahoppers and leaf hopper nymphs. Plant bugs prefer legumes to cotton and usually are found in large numbers in areas of alfalfa or areas providing wild hosts. Lygus bugs are attracted to succulent growth; their feeding results in shedding of squares and small bolls, stunted growth and boll deformation. Feeding damage to small bolls is often characterized as small black spots or small sunken lesions. The feeding that causes these spots or lesions may or may not penetrate the boll wall and damage developing seeds or lint. Damage to blooms appears as black anthers and puckered areas in petals.

Management and decision making. The need for lygus bug control is determined by their abundance in relation to the fruiting condition of the cotton plants. Fields should be inspected for lygus bugs at 4- to 5-day intervals using a drop cloth. Lygus are more reliably sampled using a drop cloth. The drop cloth method uses an off-white cloth measuring 36 x 42 inches (on 40 inch rows). Staple a thin strip of wood, approximately 1 inch wide, to each short side of the cloth. Select a random site in the field and unroll the cloth from one
row over to the next row. Mark off 18 inches on each row bordering the cloth and vigorously shake all the plants within that area. Two 1.5 row-foot sections (3 feet total) will be sampled simultaneously for insects. Count the number of lygus bug adults and nymphs that fall on the cloth. Repeat the process in at least 20 locations in the field (60 feet of row sampled). If the results show that populations are close to threshold levels, or if the field is very large (> 100 acres), sample more areas to increase the confidence in the results. During the first week of squaring, the economic threshold is 1 lygus bug adult or nymph per three feet of row combined with less than 90 percent square set. In the second week of squaring, the economic threshold is 1 lygus bug adult or nymph per three feet of row combined with less than 85 percent square set. In the third week of squaring, the economic threshold is 1 lygus bug adult or nymph per three feet of row combined with less than 75 percent square set.

SUNFLOWER
April planted sunflowers are now starting to bloom. The sunflower moth is a key pest of this crop which can greatly reduce yield potential. Treatments for this pest should begin when 20% of the heads start to bloom and sunflower moths are present in the field. Count any head as blooming if the ray petals can be observed. Confectionary flowers tend to bloom faster than oil seed flowers. Last year Greg Cronholm, IPM Agent in Plainview, took bloom counts in a confectionary field and found the following bloom pattern shown in the table below:

As one can see when confectionary sunflowers hit 5% bloom they should be treated the following day. If one waits til the field is at 20% bloom and is delayed by a day the field will be at 40% bloom. Many insecticides are labeled for control of sunflower moth. Currently listed in our Sunflower Insect Pest Guide are Furadan ®, Sevin ® ,Lorsban ®, Bacillus thuringiensis, Baythroid ®, endosulfan, Asana ®, Karate,® methyl parathion and Socut X-TRA ®.

West Plains IPM Update is a publication of the Texas Agricultural Extension Service IPM Program in Hockley and Cochran Counties.

Insects, Weeds and Plant status discussion and question/answer.
1 CEU for all TDA Pesticide Applicators

Provided by the Texas Agricultural Extension Service IPM Program in Hockley and Cochran Counties, For more information call Kerry Siders, EA-IPM at 894-2406

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