Sorghum Tips

For Texas High Plains, Headworms are Here, Complicating Sugarcane Aphid Control

This tip was provided by:

Calvin Trostle, Extension Agronomy, Lubbock, 806-746-6101, ctrostle@ag.tamu.edu

High Plains

For Texas High Plains, Headworms are Here, Complicating Sugarcane Aphid Control

As much as I would like to talk about something else in this Sorghum Tip, last week I cautioned High Plains growers to guard against complacency regarding sugarcane aphid.  If you are a sorghum grower downstate, bear with us we try to reduce the possibility of train wreck in some High Plains fields.  Any field that I have looked at that was treated with either Transform or Sivanto has had excellent control (to my knowledge almost all were by ground rig).  I have noticed, however, a higher than normal number of winged SCA in several fields.  These have to be watched as they can lead to colonies.  Furthermore, SCA counts in our AgriLife Lubbock Center SCA tolerance test was completed on Sept. 2, but I was back in the field on Sept. 6 and there was a 10-fold increase in the amount of honeydew in just five days.

So keep scouting sugarcane aphid in the High Plains… especially as AgriLife Extension entomologists are reporting significant numbers of headworms in some fields.  You may have fields where they were active down in the whorl; when those leaves unfurled they were a mess.  But as long as worms don’t feed deeply in the whorl and damage the developing head, this is only cosmetic.  Now the headworm complex is moving into the head and in numbers and worm size that is above threshold.  This is a combination of sorghum headworm (cotton bollworm on cotton, or corn earworm on corn) and fall army worm.

If these worms are present at or above threshold in your field it will potentially complicate SCA control.  This is because you may have to go to a pyrethroid and/or Lorsban to get control.  And though this can also reduce SCA, you are likely eliminating your beneficial insects that fight SCA (adult lady beetles and lady beetle larvae; green lacewings; and syrphid flies, which I learned this week some locals call hover flies, or even ‘hoover flies).  This could make SCA even worse.

For further information on control of SCA as well as headworms (and also sorghum midge, if present) read about the control strategies in the Aug. 26 & Sept. 1 newsletters from Texas A&M AgriLife entomology’s “Focus on Entomology” newsletter at http://focusonagriculture.blogspot.com/

Two further thoughts:  1) Some growers are report receiving advice to include Lorsban in their SCA sprays of Sivanto or Transform—DON’T DO IT!  You could make things worse; 2) I watched an airplane sprayer treat SCA in southwest Hale County Wednesday:  I cringed to see the drift, the inability to cover the ends of the field due to power lines, etc.  There is just no way the farmer will get uniform SCA control.  What I saw would increase my resolve to use a ground rig with high carrier volume to spray every possible acre that needs treatment.  If you are now faced with spraying for SCA if you can cover even some of your acres with a ground rig, I encourage you to do so.

Abundant, even Excessive Rains, in the Texas High Plains—Implications

This tip was provided by:

Calvin Trostle, Extension Agronomy, Lubbock, 806-746-6101, ctrostle@ag.tamu.edu

High Plains

Abundant, even Excessive Rains, in the Texas High Plains—Implications

1. Are your weeds boing berserk?

The latest sorghum is moving toward boot stage though cooler, cloudy weather may have slowed it down.  Pigweed has become a problem in some fields.  Every weed control herbicide you put out earlier is giving reduced or even little control due to rain after rain in some areas.  You may have pigweed that is already 6” or even 12” tall.  Options for late season weed control could include Huskie (up to 30” tall grain sorghum, but before flag leaf emergence) or Peak (up to 30” tall, but prior to heading).  There really aren’t any tank mix options.  Fortunately for some growers the canopy is thick so that may suppress some weeds.  I have only given a few details on these two chemicals, so ensure you read the label.  There might be another rescue option or two, but I am not sure what that would be.

 

2. Some grain sorghum is showing pale green to light yellow color on younger leaves coming out of the whorl (Fig. 1).

Due to all the rain, any N applications you made may have been diluted and move downward such that you are now insufficient in nitrogen.  Given time, N will move to these younger leaves and they will green.  This is not to be confused with the yellow striping between the leaf veins, which is iron deficiency.  Lack of iron (Fe) can occur in waterlogged conditions, but I have not seen this yet in the current High Plains grain sorghum crop.

Fig. 1.  Light yellowing of most recent leaves may indicate temporary nitrogen deficiency due to leaching of nitrogen in the soil.

Fig. 1. Light yellowing of most recent leaves may indicate temporary nitrogen deficiency due to leaching of nitrogen in the soil.

By the time sorghum heads out about 70% of N that the plant will require (if it is available) will already be in the plant.  Some producers have asked about foliar feeding, but that is only a viable consideration when you can readily deliver a few pounds of N to the crop and absorb the much higher cost per unit of N that foliar feeds represent.  For an acute deficiency, a producer looks for a way to deliver a larger amount of N, but we are so late in the season with most sorghum that we don’t normally recommend larger N applications now.  Applying a small amount of N now might help, but for the plants represented in Fig. 1, I would say ‘do not apply.’  If you are spraying for sugarcane aphid and your crop is pale, then inquire if a few pounds of N in a product that will be compatible with Sivanto or Transform.

 

3. Sugarcane aphid in the High Plains is a concern (I hope this is not a surprise)

SCA is now surely present in all counties even if it hasn’t been reported.  Infestation levels range from thousands per leaf (most likely the central and lower South Plains and to the east) to first observations the past 10 days (northwest South Plains, Texas Panhandle, eastern New Mexico).  With all the rains we have had, based on previous years observations, we might have expected this to set sugarcane aphid back.  It didn’t happen.  SCA were reaching economically damaging levels shortly after some of the recent rains.  Also, producer here have heard how much less SCA was downstate, but at Dr. Pat Porter, AgriLife Extension entomologist, Lubbock, noted, the entomology group believes that the High Plains are different conditions than downstate.  Finally, some of our IPM agent newsletters have mentioned that there have been, at least up to about two weeks ago, few beneficial insects present.

Bottom line for SCA, Texas High Plains, 2017:  Do not be complacent.  You must scout your fields.  Tolerant sorghum hybrids may help, but they are not immune, and are all susceptible to SCA at some level.  The fact that we have all heard that SCA was less a problem downstate means nothing.  The farmer that has a field in Lubbock Co. that recently averaged well over 1,000 aphids per leaf learned this the hard way.  I am pleased to report that several of my own SCA sprays (Sivanto, 5 oz./A, 12 gallons/A with my backpack sprayer), show no re-infestation of SCA almost 3 weeks later.  Also, if you are only after SCA, do not add Lorsban to your spray (some growers report receiving this advice from applicators).  Lorsban, though inexpensive, is not needed for aphids, but only kills your beneficials, and you in fact may be worse off.

Grain Sorghum Harvest Aids and SCA

This tip was provided by:

Ronnie Schnell, Cropping Systems – Statewide, College Station, ronschnell@tamu.edu

Statewide

Grain Sorghum Harvest Aids and SCA

A common question in recent years is whether or not to use a harvest aid, such as glyphosate, if sugarcane aphids are present. Do not use a harvest aid or desiccant as a tool to manage sugarcane aphids. It is uncertain how the aphid will respond following desiccation of the plant. Aphids could move toward the head and create harvest problems. If aphids are at or approaching threshold and could become problematic at harvest, consider an insecticide application. If you need or typically use a harvest aid, follow standard protocol for harvest aid use in sorghum. Keep in mind that pre-harvest intervals differ between insecticides (14 days for Sivanto and Transform) and harvest aids (7 days for glyphosate).

Desiccating leaf and stem tissue and stopping growth of immature grain heads can result in uniform grain moisture and more favorable harvest conditions for grain sorghum.  Sodium chlorate and glyphosate are commonly used products labeled for pre-harvest or harvest aid use in grain sorghum. The primary physiological criteria for application include seed moisture below 30%. Sorghum hybrids reach physiological maturity near 30% moisture, which is best determined by identifying black layer in the seed (Figure 1). Remember that kernels near the base of the head mature last. Seed moisture content can differ as much as 6% from the top of the head to the bottom. Also, tiller heads will likely mature later than primary heads and may contribute significantly to yield. Applying products to soon can reduce grain yield and quality. A summary of grain sorghum harvest aids and their uses can be found at: http://publications.tamu.edu/CORN_SORGHUM/PUB_Harvest%20Aids%20in%20Sorghum.pdf

sorghumtip7:28:17

Figure 1. Sorghum kernels in various stages of maturity harvested from the same head from the most mature (1) to the least mature (5). The black layer is first readily visible in (3) and becomes more distinguishable as the seed loses moisture. Do not confuse black layer, which develops where the seed is attached to the plant (bottom end when in the head), with the black dot on the opposite end of the seed.

Recent High Plains Grain Sorghum Replanting

This tip was provided by:

Calvin Trostle, Extension Agronomy, Lubbock, 806-746-6101, ctrostle@ag.tamu.edu

High Plains

Recent High Plains Grain Sorghum Replanting

Starting the last week of June there was widespread storm damage on cotton and grains in the Texas High Plains, and a lot of cotton was lost.  Numerous calls from producers noted the dilemma some felt about planting grain sorghum primarily due to sugarcane aphid concerns.  Fortunately, among those that replanted to grain sorghum, finding a purported SCA-tolerant hybrid was a priority (glad you asked!), grain prices are up (some central South Plains, or Lubbock area, pricing now sets grain sorghum bu/A pricing = Dec17 corn), and many producers ultimately recognized that replanting grain sorghum was the right thing to do.  Those growers that put two sugarcane aphid sprays in their budget probably overdid the expenses (though growers in the NW South Plains from last year have major damage fresh on their minds).

Be sure to review the SCA management guidelines outlined in the June 8 Sorghum Tip (have you watched the nine short videos yet?—now is a good time).

If you have late-planted grain sorghum or have replanted the crop…

 

Dicamba in Grain Sorghum

Dicamba (most commonly as Banvel or Clarity, but in many generics) along with 2,4-D have almost become anathema to many grain sorghum growers.  Past experience of damaging the crop due to injury of twisting, rolled leaves, leaning, etc. that growers don’t like the appearance of and, yes, actual injury to the all-important growing point which can lead to significant loss of grain yield (blasting of heads).  A grower in Lubbock Co. calling on Wednesday looking for quick options to control small pigweed (Palmer ameranth or carelessweed) assured me he knew full well the potential injury from dicamba.

But many of the errors of dicamba and 2,4-D injury can be attributed to diverging from the label.  I have written before in Sorghum Tips the connection between the label timing of dicamba (and 2,4-D) applications and growing point differentiation, i.e. once grain sorghum is past about the 5-leaf stage (actually probably 6-leaf stage) or 8” tall, dicamba must move to drop nozzles or hooded sprayers, and all applications completed by 15” tall.  This stage of growth at 5 & 6 leaf is before the head starts to form.  After that, head injury may occur with over-the-top sprays, but you won’t know until the head emerges and begins to flower (or not).  Otherwise, dicamba at 3-5 leaf stage (label recommendation) is still a good broadleaf weed control option, especially in the face of herbicide tolerant weeds.  You know this if you are a cotton farmer in the Texas High Plains as over 60% of the cotton planted this year is some type of dicamba-tolerant (Extend) variety.

Furthermore, since there is so much dicamba-tolerant cotton in the area, the risk of off-target drift is reduced.  The above farmer noted there was no non-dicamba cotton within at least 1.75 miles of the field he called about spraying dicamba on grain sorghum.  Also, consider whether some of the physical drift minimization technology (spray tips, etc.) developed and recommended for use in dicamba and 2,4-D tolerant cotton might help you manage any dicamba and 2,4-D use in your grain sorghum.

Extreme Heat and Sorghum Flowering

This tip was provided by:

Ronnie Schnell, Cropping Systems – Statewide, College Station, ronschnell@tamu.edu

Statewide

Extreme Heat and Sorghum Flowering

High temperatures have affected many portions of Texas in recent weeks and again during the current week. In some regions of Texas, grain sorghum was in critical growth stages that could be affected by high temperatures. Sorghum is known to have good heat and drought tolerance compared to many other crops. However, sorghum is sensitive to extreme temperatures.

Sorghum is sensitive to extreme temperatures during a 10-day period before and 15-day period after pollination. The period 5-10 days before flowering is critical for final floret development. The period 5 days before to 5 days after flowering is also sensitive. It is during this time that pollen shed, fertilization and embryo formation occur. Floret viability, pollination and embryo development can be reduced by temperatures from 97 to 100°F. Some hybrids are more tolerant to heat stress than others. Heat stress during grain set can reduce grain weight. Timing and duration of heat will determine the final impact on yield. Several days of extreme heat (>100°F) or many consecutive days of moderate heat during critical growth periods may result in some yield loss.

Avoidance is the about the only way to manage heat stress in sorghum. Early planting and choosing hybrids with maturity appropriate for your environment are the best to avoid heat stress in Texas. Also, pay attention to hybrid performance trials in your region. Hybrids that consistently perform well in your region are likely better adapted to handle biotic and abiotic stresses encountered in Texas.

sorghumtip

Ensuring Later-Planted Sorghum Growers have Sugarcane Aphid Resources

This tip was provided by:

Calvin Trostle, Extension Agronomy, Lubbock, 806-746-6101, ctrostle@ag.tamu.edu

Statewide

Ensuring Later-Planted Sorghum Growers have Sugarcane Aphid Resources

For grain sorghum planted since mid-April in the Concho Valley, North Texas, and the High Plains, the good news is that it appears the downstate reports of sugarcane aphid are still well distant.  The longer this remains the better.  For this planted sorghum as well as forthcoming High Plains sorghum the “First Things” SCA information from Texas A&M AgriLife entomologists are below.  Though you may be concerned about cost of treatment—and these management guidelines emphasize the need for treatment when thresholds are met—you can reduce the potential that those costs spin out of control (money you spend on another spray; the money you lose on a damaged crop) by appropriate scouting and timely spraying.  One of our High Plains AgriLife Extension IPM agents, Kerry Siders (Hockley/Cochran/Lamb Counties) has noted “A good first shot can eliminate the need for a second spray.”

  • Current SCA control recommendations from AgriLife Extension entomology colleagues.  This includes the “Scout Card” at http://lubbock.tamu.edu/files/2016/03/ENTO-047.pdf (recommendations unchanged from 2016).  There has been a move within AgriLife to reduce the aphid thresholds downstate to the lower SCA numbers in line with High Plains recommendations.
  • Texas Sugarcane Aphid News blog at http://txscan.blogspot.com/  Of particular interest on the blog, scroll down to the Feb. 20, 2017 entry which lists 9 AgriLife videos (41 minutes total) pertaining to all aspects of SCA.  I highly recommend all sorghum producers in the High Plains take an hour to view these.
  • Other SCA and sorghum insect management info. is found at http://www.texasinsects.org/sorghum.html,

Scouting for Sugarcane Aphids

This tip was provided by:

Ronnie Schnell, Cropping Systems – Statewide, College Station, ronschnell@tamu.edu

South and Central Texas

Scouting for Sugarcane Aphids

Sugarcane aphids are currently found in many sorghum fields in the southern and coastal areas of Texas. The distribution of the aphid is expanding north into central Texas. Sugarcane aphid distribution is being tracked at: https://www.myfields.info/pests/sugarcane-aphid. This map shows where the aphid has been detected but not the level of infestation.

Many fields have been sprayed in the Rio Grande Valley and Coastal Bend. Some fields in the upper Gulf coast are reaching threshold and will require treatment. It is important to scout frequently and thoroughly once aphids are detected. Recommended scouting methods differ for south and central Texas compared to the High Plains region of Texas. Specific recommendations can be found at: https://www.myfields.info/sugarcane-aphid-texas-sorghum-0

When scouting, make sure to identify the aphid. Yellow sugarcane aphid, corn leaf aphids or greenbugs may be present. Thresholds and control methods will differ for these pests compared to sugarcane aphids. If chemical control of sugarcane aphids is needed, keep in mind pre-harvest intervals and spray restrictions. Transform cannot be used from 3 days pre-bloom until after seed set.

If you have planted hybrids with resistance or tolerance to sugarcane aphids, keep in mind that the hybrid is not immune to sugarcane aphids and needs to be scouted. Sugarcane aphid populations may take more time to reach economic threshold, if at all.

West Texas & Early Planting to Minimize Potential Sugarcane Aphid Impact

This tip was provided by:

Calvin Trostle, Extension Agronomy, Lubbock, 806-746-6101, ctrostle@ag.tamu.edu

West Texas

West Texas & Early Planting to Minimize Potential Sugarcane Aphid Impact

United Sorghum Checkoff Program agronomist Dr. Brent Bean notes caution about planting grain sorghum too early.  Producers by now across Texas have heard from AgriLife entomologists to “plant outside the normal” window, which is primarily “plant early” to reduce your potential exposure to sugarcane aphid, especially when plants are at the vulnerable seedling stage.  That stage-of-growth vulnerability should be partially covered by recommended insecticide seed treatments.

Dr. Bean notes that early planting is not without question.  Yes, you can plant too early thus grain sorghum is slow to germinate, slow to emerge, and may not provide you the protection you expected.

“There are reasons why optimum planting dates for sorghum exist, and these should not be ignored.  Optimum planting dates are based on soil temperature, timing of seasonal rainfall and daily maximum temperatures, risk of insect infestation, and length of growing season,” Dr. Bean notes.

In the High Plains region over the years, millions of dryland sorghum acres have been planted after May and June rainfall.  The outcome is May-June rainfall charges deep soil moisture then September rains (the second wettest month of the year in most West Texas counties) carry the crop through to maturity.

Grain Sorghum Germination and Soil Temperature

Again Dr. Bean notes, “One of the first considerations for early planting should be soil temperature.  The cooler the temperature the slower the sorghum will germinate and emerge.  Most agronomists suggest waiting to plant sorghum until the minimum daily soil temperature is 60°F (usually 2-4” depth) and the forecast for the next 10 days is for warm weather.”  Slightly cooler temperatures may be sufficient provided the weather is clearly warming.

How does the above sorghum germination temperature compare to cotton?  The optimum planting target for cotton is a 10-day average soil temperature (not minimum) of 65°F at the 8-inch depth.  Sixty degrees for sorghum is likely a more shallow temperature, and that is a minimum.  A 4” depth, there is some daily fluctuation, but this would point to an initial sorghum planting temperature that is probably 7-10 days earlier than cotton.

Another safeguard against too-early grain sorghum planting:  do not plant grain sorghum any earlier—regardless of soil temperature—than the point which is two weeks after your last average 32°F temperature.  So, if your county’s last 32°F is April 3 (Dawson Co.) then do not plant sorghum any sooner than April 17—BUT ONLY IF soil temperatures are adequate (the West Texas Mesonet reports the Lamesa April 13 bare soil temperature minimum at 4” is 61°F, but that could be due to April 12 rains).

Here are these last average 32°F dates for selected West Texas counties:

Tom Green, March 28               Yoakum, April 5                        Gray, April 13

Taylor, March 24                        Lubbock, April 6                       Moore, April 18

Wilbarger, March 30                 Swisher, April 14                       Ochiltree, April 25

Collingsworth, April 1                Bailey, April 17                          Dallam, April 23

Dawson, April 3                          Deaf Smith, April 19

So, early sorghum planting to minimize potential exposure to SCA is probably not worth the risk a poor or slow growing stand.  Companies may have hybrids that have tolerance of cooler soils, but then you may lose proven yield potential and/or your possible SCA tolerance in the hybrid.

Early planting may also reduce the risk of other insect damage. In most regions, headworms and midge issues are much less with early planting.  From a SCA management standpoint this is important because many of the insecticides used for these two pests will cause SCA populations to flare.

In summary, Dr. Bean notes early planting of sorghum for managing SCA is an effective IPM tool and should be considered.  “However, do not disregard sound sorghum agronomic practices. Simply moving the planting date up by a couple of weeks can make a significant difference in managing SCA.”

Planting Grain Sorghum: II. In-row Spacing

This tip was provided by:

Calvin Trostle, Extension Agronomy, Lubbock, 806-746-6101, ctrostle@ag.tamu.edu

Statewide

Planting Grain Sorghum:  II. In-row Spacing

In a previous Sorghum Tip, I discussed row spacing (see http://texassorghum.org/sorghum-tips Feb. 20, 2017).  Now what about spacing of seeds within the row?

On this smaller scale of about two to six inches within the row, it may seem that the uniformity of spacing is not that important.  Yes, it is true that the root system, for example, will basically still explore the same area and leaf area will be about the same.  Some hybrids, though, do respond differently to spacing around the individual plant with more tillering than others.  This can be a positive effect (a plant accounts for extra space and yield potential by tillering to compensate for a gap in the row) and negative (excess tillering is not desirable in moisture-limited production).   Research beginning in the early 2000s from Dr. Bobby Stewart’s program at West Texas A&M demonstrated that for West Texas dryland conditions suppression of tillering by placing 4 to 6 seeds (thus subsequent plants) within 1.5” or less would essentially eliminate tillering.  Resulting yields tended to be higher (the plant does not direct resources into unproductive tillers) than uniform spacing, but the potential for less shading of soil of clumped plants may lead to more weeds and higher evaporation of soil moisture.

Still having uniform spacing with the row is a plus.  We are most immediately concerned about larger gaps of 12” or more—they are obvious, especially if you are planting 3 to 6 seeds per foot of row.  But the same principle applies like I discussed in row spacing, uniformly distributed plants is favorable.

The faster you plant on rough ground you will also lose incrementally some of your uniform spacing in the seed drop.  I am not the first one to advise producers to “slow down” when you are planting.

I have already planted my grain sorghum.  I will consider this next year…

Actually, when your crop is young, it is a good time to evaluate the stands you have in individual rows.  Do you have skips?  Do you have a row that looks thick?  Or thin?  Usually you can tell from the tractor tire track ribs which direction the planter was moving so you know which row unit of the planter may have thickly or thinly seeded row.  The planter unit needs to be checked for a malfunction.  If you are using a plate planter you can’t expect quite the uniform spacing (or even favorable control of seed drop), but for planters that meter seed in an air-vacuum system, you should expect all rows to very closely drop the same number of seed.  And if you see a row that departs from the general appearance, you need to check that planter unit.

Planter Unit Seed Drop Confirmation

In testing on a late model John Deere 8-row planter at one of our AgriLife research facilities, I found that two rows dropped 17% or more seed than they should have, and one rows was -20% from what was targeted.  Pending the production conditions this creates a potentially non-agronomic plant population.  I recommend that farmers, once they have their seed on hand for grain sorghum—or any other crop—set the planter up, turn the drive wheel a set distance and catch seed to calculate the number of seeds per foot.  How does this match with your planter book?  In this case, a correction can be made before you go to the field, otherwise you await the stand to see if one of your planter units may be off.  For an individual row with the seeding rate off, that is like having the whole field at that population in that row.  You have too many or too few plants.  It needs to be corrected.

Sugarcane Aphid Management Suggestions & Resources

This tip was provided by:

Calvin Trostle, Extension Agronomy, Lubbock, 806-746-6101, ctrostle@ag.tamu.edu

Texas High Plains

Sugarcane Aphid Management Suggestions & Resources

This edition of Sorghum Tips deals with SCA management in the Texas High Plains.  The information may also be relevant for the Concho Valley and Rolling Plains, though the information presented here was not developed in those regions.  There are differences in the High Plains recommendations vs. what we published in the March 3, 2016 Sorghum Tips for South & Central Texas (see http://texassorghum.org/sorghum-tips for Extension’s Dr. Robert Bowling’ comments).

Instead of reproducing here the details of current SCA recommendations for Texas High Plains grain sorghum, I refer you to the direct writings of Texas A&M AgriLife Extension’s High Plains entomology group led by Dr. Pat Porter, Lubbock.  Consult the Texas Sugarcane Aphid News blog at http://txscan.blogspot.com/  The March 2 posting is the first installment of advice with the topics:

  • Sugarcane aphid will most likely return at some level for renewed infestation of High Plains grain sorghum, so be prepared and plan for it.
  • Beneficial insects cleaned up the overwintering aphids in 2016, but what does this mean (or not mean) for 2017?  Read about early observations on the level of current beneficial insects observed in wheat.
  • What about 2017?  Certainly, early planting remains a primary consideration.  Late planting in 2015 was also a good strategy, but that didn’t hold in 2016.
  • Seed treatments are cheap insurance.  It appears that 45 days of protection can be obtained with neonicotinoid seed treatments.  This is especially helpful for seedling sorghum, but all sorghum regardless when planted, should use this strategy.
  • “Resistant” or “Tolerant” grain sorghum hybrids are still susceptible.  No grain sorghum hybrids have been shown to be able to keep SCA numbers below treatment thresholds, but they can slow the rate of SCA population increase.  All of these hybrids require scouting.
  • Additional information for SCA will be posted to the Sugarcane Aphid Network blog soon for the Texas High Plains.  Further topics will include initial treatment thresholds, insecticide rates and efficacy, and economic thresholds for a potential second spray.  Remember, High Plains SCA thresholds are lower than South Texas based on research to date.

Sugarcane Aphid Management Videos for the Texas High Plains

The Texas A&M AgriLife Extension entomologist team working on grain sorghum (Porter, Bynum, Reed Kesheimer) posted nine videos ranging from 3 to 8 minutes in their February 20 update.  See them all at http://txscan.blogspot.com/  Topics include early planting, “resistant” hybrids, thresholds, timing, insecticides to prevent sticky harvest issues, SCA effects on forage stalk quality, etc.

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