Higher temperatures prevailed most of
the week accompanied by windy conditions. Grain sorghum has made excellent progress during the past week and much of it is blooming. A few headworms can be found at this time but nothing to get alarmed about. Be on the look out for grasshoppers. A number of fields and/or field margins required treatments this week for grasshoppers.

Cotton ranges in growth from still in the bag to matchhead square stage. The majority of the cotton planted in the Concho Valley is in the cotyledon to 3rd true leaf stage. Remember, you have a "short window" when applying Roundup® to Roundup Ready® cotton.

Thrips numbers seem to be decreasing and cotton fleahoppers and cotton aphids are on the increase. This is the first year in several years that cotton aphids have made their presence this early in the season. Producers are encouraged to monitor their cotton fields closely for cotton aphids and fleahoppers. Both of these insect pests can delay maturity and we are already ten days behind schedule in many cases.

Much of the cotton planted in the Concho Valley is planted to Roundup Ready® cotton varieties and most of these fields will require Roundup treatments soon. Remember glyphosate should be applied to Roundup Ready® cotton prior to the 5th true leaf stage or when the 5th true leaf is no larger than a quarter size.

Rains and better moisture conditions have increased our weed problems tremendously. Some producers planted Roundup Ready® cotton and many others planted conventional varieties. Be considerate and courteous of crops planted across the turnrow from your Roundup Ready® cotton.

There are two types of herbicide drift, Physical Drift and Vapor Drift, with Physical Drift being the primary culprit. Usually only 2,4D hormone type herbicides are volatile and will move by vaporization. Roundup® drift is by physical drift. Physical drift is dependant upon three factors: 1) wind speed; 2) nozzle size; and 3) boom height. To help reduce physical drift: 1) DON'T spray with winds more than 10 mph; 2) USE a course spray (large droplets); and 3) AVOID aerial applications in sensitive areas.

REMEMBER: The higher the pressure, the smaller the droplet size, the larger the drift potential.

Factors in the prevention of a misapplication are: 1) DON'T assume your sprayer is calibrated; 2) Check nozzle tip output daily; 3) CLEAN sprayer often; and 4) KEEP records of chemicals used in the sprayer. To reduce physical drift potential: 1) DECREASE spray pressure;

Symptoms of Roundup® Damage

COTTON APHIDS Roundup Ultra®, Rodeo®, Ranger®, Touchdown®, Liberty® and others effect the Amino Acid Synthesis. Plants treated with glyphosate or sulfosate turn yellow in 5 to 7 days, then turn brown and die in 10 to 14 days. Glufosinate acts more quickly in 3 to 5 days. An individual plant may have dead tissue, yellow tissue and green tissue at the same time. Extremely low dosages of Roundup® can cause leaf puckering and stunting of the plant.

Hot spots of cotton aphids were found in several irrigated cotton fields in Wall and Veribest this week along with two cotton fields in Norton and Winters communities. Current weather conditions are ideal for the rapid development of aphid infestations so be onthe look out. Monitor your fields regularly. Aphids are usually found in the underside of leaves, but right now they are on stems and terminals as well. Watch closely because predator numbers are very low at the present time and aphids can cause significant damage to seedling cotton.

We were blessed in many areas with some rainfall and these improved moisture conditions have encouraged lots of weed growth. As producers plow out or burn down these weed hosts, fleahoppers will move to squaring cotton. Fleahoppers can and do delay crop maturity. Once your cotton reaches the 6th to 7th true leaf stage, monitoring for fleahoppers and square retention is very important.

During the first week of squaring, the economic threshold is 25 to 30 cotton fleahoppers per100 terminals combined with less than 90 percent square set. In the second week of squaring, the economic threshold is 25 to 30 cotton fleahoppers per 100 terminals combined with less than 85 percent square set. Starting with the third week of squaring up to the first bloom, the economic threshold is 25 to 30 cotton fleahoppers per 100 terminals combined with less than 75 percent square set.

In cotton planted after May 15, treatment decisions should be made during the first week of squaring, if possible, to avoid a potential bollworm outbreak resulting from the destruction of beneficial insects and spiders. As plants increase in size and fruit load, larger fleahopper populations can be tolerated without yield reduction.

Grasshoppers are moving into cotton and grain sorghum fields in some areas. The largest numbers are moving out of pastures or rangeland. Although there are over 100 species of grasshoppers known to exist in the state, the following six species probably cause 90 percent of the damage to crops and home landscapes: differential grasshopper, red-legged grasshopper, migratory grasshopper, two-striped grasshopper, Packard grasshopper and the Lubber grasshopper. Most of what we are seeing right now are the differential and the two-striped grasshopper.

Control measures are most effective when grasshoppers are small. Where large numbers of grasshoppers continue to move into the edge of cotton, control can be difficult. Border treatments around the field can sometimes reduce excessive stand loss. Producers are encouraged to monitor grasshopper movement into field borders from nearby pastures, waterways and road ditches. The economic threshold for treating grasshoppers ins field margins is 20 or more grasshoppers per square yard. Within a field, treatments should be initiated when 10 or more grasshoppers are detected per 3 row feet. Some insecticides labeled for crops, pastures and homestead sites are listed below.

Cotton

Bidrin 8 at 4 oz.- 8 oz. per acre,
Lorsban 4 E at ½ to 1 pt./acre, malathion (Atrapa ULV 9.9 at ½ to 3/4 pt./acre or Fyfanon

Sorghum

Baythroid 2 at 1 gal./64 acres, Warrior T 2.56 to 3.84 ozs./acre, Sevin XLR Plus at 1 to 3 pts./acre, Sevin 80S at 2/3 to 1 7/8 lbs./acre and dimethoate 4E at 1 pt./acre.

Pasture

The economic threshold for treating pastures is when 8 to 40 grasshoppers, greater than ½ inch, are detected/square yard.

Malathion 57 EC at 1 ½ to 2 pts./acre (no grazing restrictions), Sevin 4F and Sevin XLR at ½ to 1 qt./acre, Sevin WPS 2/3 to 1 1/4 lbs./acre (14 day interval between application and grazing), Orthene 75 WSP at 2 to 2 2/3 oz./acre (Beef cattle may graze treated pasture on the same day of application, but must be removed from treated area at least one day before slaughtering).

Lawns & Homestead Sites

Bayer Advanced - Cyfluthrin, Tempo - Cyfluthrin, Spectracide "BUG STOP" - Permethrin, Spectracide Triazicide - Lambda-Cyhalothrin, Orthene, Sevin 80 WSP, Sevin XLR Plus, malathion and Neem.

The weekly turnrow meetings will begin next week, Tuesday morning, June 25th, 9:00 a.m., at Wall Coop. The second meeting will be Wednesday morning, June 26th, 8:30 a.m. at Ballinger Coop.

The "IPM Updates" will begin this coming Monday, June 24th. The telephone number to call is 365-2642. This update will give producers a general insect and crop report for the different areas in Runnels, Tom Green and Concho Counties that is being monitored by the cotton scouts. I would encourage you to use this service. This allows you access to the information at your convenience. If it is not used this year, we will discontinue it next year.

Educational programs conducted by the Texas Agricultural Extension Service serve people of all ages regardless of socioeconomic level, race, color, sex, religion, handicap or national origin. The information given herein is for educational purposes only. References to commercial products or trade names is made with the understanding that no discrimination is intended and no endorsement by the Cooperative Extension Service is implied.