The Amalgamated Sugar Co. LLC

Mini-Cassia District

May 10, 2000

INSECT CONTROL

With the warmest winter on record just behind us and the start of a fairly warm spring, we have already experienced some of the potential insect pressures which could be expected from such favorable over-wintering conditions.

CUTWORMS

The survival of cutworm eggs and their early hatch has evidenced itself in some of the problems which growers have faced in trying to figure out why small, hardly emerged seedling beets have disappeared in a few fields. Also why some beets simply haven't emerged, and when investigated only stems of a hypocotle are found with no meristem tissue left. Upon further investigation, cutworm have been found and treated.

This continues to be a problem in some field situations. If stands aren't as they should be with some long skips in rows and skips in adjacent rows in an area of a field which normally produces good emergent stands, one should further investigate.

The conditions contributing to the presence of the cutworm seem to be grain fields which were only disked and / or chiseled last fall, fields which were alfalfa last season, or fields bordering such fields as well as any pivot with corners that were in grain or similar vegetation last year. Obviously the eggs overwintered in these conditions and as they hatched have started feeding or have moved into beet fields seeking food or are moving across beet fields and grazing as they go heading for better feed.

Treatment with Lorsban 4E @ the rate of 1 pint to 1.3 pints per acre in a 7 inch band have been effective. Asana XL has been equally effective and can be mixed with the post- emergent herbicide applications. The rate of 3 to 4 oz. per acre banded over the row have been doing the job.

We need to keep paying attention to this pest even yet this season. If you have not fully canvassed some of your fields you may find some holes when you finally run the cultivator over them.

ROOT MAGGOTS

For the past few years we have monitored the emergence of the root maggot fly in the Mini-Cassia area by setting out a route of strategically placed sticky stakes in growers fields around the valley and taking captured fly counts every two days. A running tally is kept for each site of a pod of stakes and this information is posted regularly as it is updated on the company web site. This years information will likewise be posted on this web site under Mini-Cassia information.

A LITTLE BACK GROUND INFORMATION

With the work done by entomologists in beet growing areas around the country as well as here in Idaho by our own university people a formula for predicting the emergence of the root maggot fly's has been determined. Basically what this entails is that the root maggot fly is cold blooded and therefore its developmental rate is proportional to temperature increases. If temperatures are higher a greater or faster development occurs and if lower a lesser degree of development happens. With higher temperatures, fewer days are required for their emergence. Conversely, lower temps. more days are required. The minimum temperature threshold for the development or metamorphoses from overwinter pupae stage into the adult fly is 47.5 degrees F. The degree days required for emergence can be computed by keeping track of the high and low temperatures beginning March 1^st. We have done this year in various sites around the valley and even though the north side is slower in collecting the 360 degree days required for emergence, at the present both north and south sides of the valley have arrived at the required degree days for emergence. This is earlier than most previous years in the immediate past.

The warmer temperatures which we've had this past April, of course have put us ahead in this regard.

Only a few flies have been spotted at the present. The weather has taken a turn down as far as temperature and this will slow emergence for the present. The sticky stake route will be put out this week and monitoring will start as soon as the conditions are requisite for fly flight. This entails the need for daytime temperatures up around 80 degrees F. At these temperatures their movement and activities, including propagating and egg laying moves along quite rapidly. At lower temps these activities are slowed.

NUMBERS OF FLIES WHICH SIGNAL NEED FOR TREATMENT

With the work started 30 years ago by C.C. Blickenstaff here in the Magic Valley and continued through the 80's and early 90's by John Gallian, Ed Bechiniski, Bob Stolz and Associates, it's been established that the collected count of 40 to 45 flies in a pod of fly stake traps is the level of economic impact, signaling the need to treat with an insecticide.

BEST TIME TO APPLY INSECTICIDE

The best time to apply insecticide is during a 20 day window around when peak fly capture, ( hence the heaviest emergence of the flies) occurs. This means anywhere from 10 days before to 10 days after. The past few years this peak fly flight has been as listed:

As previously stated the time table for flight and peak capture this year could be earlier as anticipated from the warmer early temperatures which we've had. Ultimately though this will depend on the weather the next three weeks.

APPROACHES TO TREATMENT AND TIMING CAN BE CRITICAL

A grower with past history of only moderate maggot populations to deal with may still be OK with the at plant applications of Counter or a application at 1^st cultivation. Growers in heavy infested areas should take a discretionary look at how well the maggot control program they have used in past years worked. The products they have used and the timing of their application are critical components of an effective program. If they have not been successful discuss the scope of your program with your fieldman and gear up for added effectiveness. So often the timing, the placement of product, a different and more effective product for certain conditions, and the initial activation of this product by incorporating it into the first inch of soil around the beet plants by simply irrigating timely can make or break effectiveness of control.

Solubility of insecticide is totally critical once maggot eggs have hatched and moved down onto the sugar beet plant root. In most soils and soils conditions Temik is the most effective in controlling the maggot, because of its solubility. Discuss the proper use of these products with your fieldman.

For additional information on root maggots, their life cycle, management strategies etc. please refer to the University of Idaho's web site at WWW.UIDAHO.EDU/

GRASSHOPPERS

We have had only a few reports of grasshopper problem in beet fields so far this season. However it is yet early. The same conditions which are favorable for heavy overwinter and emergence of cutworm and rootmaggots have made it favorable for hoppers also.

The report from the county extension offices is that the BLM and APHIS and other affiliated government agencies have put together a plan to assist farmers in coping with the potential grasshopper problem. The scope of the potential problem can only be realized if one remembers 1985 when government spray planes traversed the valley for weeks spraying for hoppers. In Minidoka Co. alone one hundred thirty four miles of production farm ground boarders BLM ground.

BRIEFLY THE PLAN IS AS FOLLOWS: BLM is gearing up to spray Dimilim 2L on BLM owned ground adjacent to crop land. The plan calls for a 500 foot border to be left next to crop land. This 500 foot border will be treated with Carbaryl baited grain. If necessary the plan also calls for alternate strip spraying up to one-half mile out from the Carbaryl treated border.

The plan doesn't include spraying on private owned crop land. This is the responsibility of the private landowner.

The agencies have hired scouts to monitor the emergence and numbers of hoppers on government lands. If a farmer has a problem developing around his crop land which he is concerned about, he can contact his local BLM office or the APHIS office, or Rob Machesnee and report the situation. A scout will be sent to the site and assessment made and treatment applied when required.

Contact Numbers: APHIS OFFICE 1-(208)-733-5119

ROB MACHESNEE 1-(208)-378-5797

SHOSHONE BLM OFFICE 1-(208)-886-2206

Scott Anderson 1-(208)-886-7266

Gary Wright 1-(208)-886-7255