But What About the Sugarcane Aphid?

We are almost into July and have not seen the arrival of the sugarcane aphid (SCA) onto sorghum in Lubbock or Crosby county. Many are wondering how this is possible and what this means for the rest of the season.

Dr. Pat Porter, Extension Entomologist in Lubbock, has posted an update to the Texas Sugarcane Aphid News website, summarizing what may be happening with the aphids this year. I've copied the text below.


From Dr. Porter:


     Given that we know sugarcane aphid overwintered as far north as Plainview, and that it was found on Johnsongrass in Lubbock County in early May, the question we are most frequently asked lately is, "Why don't we have sugarcane aphids yet?"

That is a good question, and I wish I could be totally certain of the answer. I suspect that our beneficial insects wiped out the overwintering aphids. We had extremely high numbers of ladybugs, syrphid flies and the other predators that went into overwintering last year after feasting on sugarcane aphids. In what should be considered to be good news, we also had fairly heavy aphid numbers in wheat this spring, but not enough to do significant economic harm. But these wheat aphids, which were not sugarcane aphids, provided food for our early season beneficial insects, which in turn were available to start munching on the overwintering sugarcane aphids in the area. This is just conjecture on my part, but it is the simplest explanation of why sugarcane aphid was here in the early season and is now gone.


The next most common question we are getting is, "When will the aphids arrive?" Of course no one knows the answer, but later is better, and growers who planted early are seeing a benefit from that practice. Last year the first sugarcane aphids found on the High Plains were discovered in Lubbock County on June 27th, and within three weeks we were scrambling to get fields sprayed. I think that last year we had some colonies beginning to build locally in late June, but, given the wide area infested a few weeks later, it is most probable that one or more flights of winged aphids came up from the south on wind or storm events. This year we probably do have some small pockets of sugarcane aphids locally. The good news is that aphids are not extremely numerous on the Gulf Coast and in the Hill Country. Our colleagues south and east of here are reporting that they have only light to moderate infestations (although some fields required treatment). They are also saying that beneficial insects are catching up to the aphid populations and decimating them. This is means there will be fewer aphids traveling on the winds and landing on our front door. If we have fewer aphids colonizing our plants then the beneficial insects we have in the system will have a better chance of suppressing those that do arrive.


I wish I could predict what will happen in the next few weeks, but of course I can't. If you find sugarcane aphids in your fields then please give us a call. The telephone numbers for your High Plains IPM Agents and Extension Entomologists are listed here. We sincerely appreciate people who take the time to call and report pest problems. 

Southern High Plains IPM Newsletter, Jun 24

Click here to read this week's edition of the IPM newsletter! 

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Southern High Plains IPM Newsletter, Jun 17

Click here to view the latest edition of the Southern High Plains IPM Newsletter! This newsletter is sent out weekly during the growing season and covers any pest issues in the Lubbock/Crosby County area. It is sent out electronically and subscription is free; just send me an email or call the office and request to be added to the list.

How to Scout for Thrips in Cotton

One of the major pests that can interfere with cotton in the first couple weeks post-emergence are thrips. Thrips damage is most severe from seedling emergence up to the fifth true leaf stage and it sometimes can be hard to spot these little critters. Blayne Reed, Extension Agent-IPM, Hale, Swisher, and Floyd Counties, and Dr. Pat Porter, Extension Entomologist, put together a short video on how to effectively scout for thrips in your cotton. Follow this link to check it out!

A thrips. Photo: David Kerns

Where We Currently Stand with the Sugarcane Aphid

A lot has happened over the last month with the Sugarcane aphid (SCA). Here is a brief timeline of what we have learned from monitoring and overwintering study results on the High Plains.

April 4

Tommy Doederlein (Extension Agent – IPM, Dawson and Lynn Counties) has reported successful SCA overwintering between Lamesa and O’Donnell. This is the second year in a row that Tommy has found successful overwintering in his cages by the SCA, although last year’s results were not conclusive. To date, this is the most northerly location of SCA overwintering.

April 25

Xandra Morris (Extension Agent – IPM, Hill County) has found winged aphids in Hill County on Johnson grass where they overwintered.

April 29

Blayne Reed (Extension Agent – IPM, Hale, Swisher, Floyd Counties) has reported successful SCA overwintering in Hale Co. Johnson grass inside the overwintering cage had adults and nymphs, while the Johnson grass outside the cage did not have any aphids. To date, this is now the farthest north we have found SCA to have overwintered, by about 80 miles.

May 3

Dr. Pat Porter (Extension Entomologist) and I found SCA on Johnson grass in Lubbock County about six miles east of New Deal. We found adults, several nymphs, and one alatoid (a nymph that will soon become a winged adult). This early May finding is almost a full eight weeks before the first sighting of SCA in Lubbock Co last year (found on June 27, 2015).

May 6

Xandra Morris (Extension Agent – IPM, Hill County) has found SCA feeding on sorghum near Itasca. There were only one or two aphids per colony, with less than 1% of plants containing aphids.

SCA on Johnson grass in Lubbock Co on May 3. Photo: Pat Porter.

Texas A&M Agrilife Extension has put together some excellent material on SCA management for grain and forage sorghum. Contact or stop by your local county extension office for more information!

Section18 request granted for SCA in sorghum

Good news!

It was just announced this week that we were granted a Section 18 request that allows the use of Transform (Sulfoxaflor) on grain sorghum in Texas for control of the sugarcane aphid, Melanaphis sacchari. This is very good news because now we have TWO effective insecticides that can be used to control SCA populations, but still preserve natural enemies. These are Sivanto and Transform. 

Very important: the user must have the label in their possession at the time of application!! 

Some label specifics: 

(compiled by Dr. Pat Porter on Texas Sugarcane Aphid News)

• Rate range: 0.75 to 1.5 oz. per acre.
• Application by ground or air (no chemigation).
• Wind speed not to exceed 10 mph.
• Droplet Size: Use only medium to coarse spray nozzles (i.e., with median droplet size if 341 μm or greater) for ground and non-ULV aerial application according to ASABE (S 572.1) definition for standard nozzles. In conditions of low humidity and high temperatures, applicators should use a coarser droplet size except where indicated for specific crops.
• Boom height for ground application: Not to exceed 4 feet.
• Carrier volume for ground application: A minimum of 5 to 10 gallons per acre - to be increased with increasing crop size and/or pest density.
• Carrier volume for aerial application: A minimum of 3 gallons per acre, but a minimum of 5 gallons per acre is recommended.

Restrictions:

• Preharvest Interval: Do not apply within 14 days of grain or straw harvest or within 7 days of grazing, or forage, fodder, or hay harvest.
• A restricted entry interval (REI) of 24 hours must be observed.
• Do not make more than two applications per acre per year.
• Minimum Treatment Interval: Do not make applications less than 14 days apart.
• Do not apply more than a total of 3.0 oz of Transform WG (0.09 lb ai of sulfoxaflor) per acre per year.
• Do not apply product ≤ 3 days pre-bloom until after seed set.

You can read the entire label for Transform at the Texas Department of Agriculture's website.