'Tis the Season for Fall Army Worms and BSM

Last year, the Fall Armyworm made is presence a little earlier than what we typically see in our area of North Carolina.  This pest is one that hay producers and pasture owners usually have on their radar in late August but reports of damage came in during July. The Fall Armyworm is a common pest in hay, especially bermudagrass, and can decimate a hay crop or pasture if left unchecked.  Another insect that often goes unnoticed in hay fields and has become a common visitor over the last few years is the Bermudagrass Stem Maggot (BSM). Although there are several types of “worms” that can be found in a hay field. The fall armyworm and stem maggot are the most important to identify and control. 

Fall Armyworm Identification: 

To determine if a field has an infestation, look for caterpillars with dark heads that are usually marked with a distinct, pale, inverted “Y” on top. Typically, you will find a black stripe down each side of their body and a yellowish-gray stripe down their back. Fall armyworms come in a variety of colors including, green, brown or black which can make identification difficult.  

Before managing Fall Armyworms, it’s important that we understand this pest’s lifecycle.  Fall armyworms are the larvae (or caterpillars) of the Ash-gray moth.  Like butterflies, the Ash-gray moth starts out as a caterpillar before going through metamorphosis.  This moth has white wings with light gray spots. Female moths lay eggs at night and lay up to several hundred that hatch within 2 to 4 days. What hatches from these eggs are what we call fall armyworms. Development from egg to fully grown Fall Armyworm requires about 2 to 3 weeks. At this point, armyworms burrow down into the soil and form pupae. In about 10 to 14 days, the moths emerge and the metamorphosis process is complete. 

While this article concentrates on pastures, note that Fall Armyworms will attack centipede and bermudagrass lawns. Armyworms feed just about any time, day or night, but are most active early in the morning or late in the evening.  Because they are active in the morning, this is a great time to scout your fields. These caterpillars will march like an army across your fields eating plant matter along the way. They tend to start from a field edge and work their way across to adjacent farms.  In severe infestations, leaves will be completely eaten with only stems left behind. This highlights the importance of scouting your fields regularly so that you can implement a control measure in a timely manner.  

Stem Maggot Identification:  

The bermudagrass stem maggot (BSM) is a relatively new pest of bermudagrass, especially when it's grown for hay. This pest is native to south Asia and was first reported in the United States in Georgia in 2010. This pest is only known to infest bermudagrasses.  The adult stage of the BSM is a small, yellow fly, which lays its eggs on the bermudagrass plant. Once the egg hatches, the maggot moves to the top of the stem, burrows into the shoot and consumes the plant tissue in the stem. This stem damage results in the death of the top 1-2 leaves while the rest of the plant remains green. The damaged leaves can be easily pulled from the stem. Grass growth will be stunted and da
mage can appear similar to frost, drought stress. 

Cutting open the stem just below the dead leaves will reveal the tunnel created by the maggot and occasionally you can find the maggot. The full-grown maggot is yellowish and about 1/8 inch long. Once the maggot completes feeding, it drops to the ground and enters the pupa stage. The adult fly later emerges from the pupae. The life cycle from egg to adult fly requires about 3-4 weeks, and there are several generations a year. 

Should I spray? 

Most research has shown that an average of 3 medium to large armyworms (about ¾ of an inch) per square foot is enough to cause significant damage to your hay crop or pasture.  This threshold may justify a control measure, such as an insecticide treatment. For stem maggots, scout fields if you notice a frosted or a burn appearance on the newest growth of the grass. 

 

What can I spray? 

If you do choose to apply an insecticide, read the label carefully to ensure it is safe to apply on hay and/or pasture! There are numerous insecticide options available so choosing the right product can be a bit overwhelming.  Several pyrethroid insecticides, such as Mustang Maxx and Karate are effective against Fall Armyworm and stem maggot but are restricted use and can only be purchased with a pesticide license.  Other products, such as Dipel and Intrepid Edge are worm-specific insecticides and are not restricted use but may be higher in cost.  Regardless of what product you choose, be sure to abide by all label specifications, calibrate your sprayer and pay attention to grazing or haying restrictions!

If you have any questions concerning pasture management, or pesticide selection please contact your local Extension office.

Assessing Pasture Condition

How productive is your pasture?  Are there current challenges?  How would you rate the overall condition?  It is important throughout the grazing season that you walk your pasture(s) and evaluate the condition.  While you can come up with indicators to rate your pasture on, there are several helpful assessments available to assist you.  One of the more well-known assessments is called Pasture Condition Scoring (PCS) developed by the Natural Resources Conservation Service (NRCS).  PCS is a systematic way to assess how well a pasture is being managed and resources protected.  It involves the visual evaluation of 10 indicators with a low score meaning the pasture has one or more challenges such as poor plant growth and/or weedy species invasion.  While a high score means the pasture is well-managed with productivity being sustained or enhanced.  Best time to evaluate a pasture is right before it is grazed.  The 10 pasture indicators (rated 1-5) that PCS uses is listed below:

·         Percent Desirable Plants

·         Plant Cover

·         Plant Diversity

·         Plant Residue

·         Plant Vigor

·         Percent Legume

·         Uniformity of Use

·         Livestock Concentration Areas

·         Soil Compaction

·         Erosion

In the PCS guide you will find very detailed descriptions for each of the indicators and a score sheet.  The PCS assessment is very thorough and highly recommended.  However, you can always simplify the process until you are ready for a more in-depth assessment.  In a recent horse workshop, we did a hula hoop activity to measure pasture condition.   Participants would randomly throw out the hula hoop in the pasture and measure the following within the hoop with a yard stick/grazing stick and by estimating:

·         Grass Height (avg. heights if they differ): ___________

·         % Bare Ground (estimate): ____________

·         % Desirable Species (fescue, etc.): ____________

·         % Weed Species: _____________

·         Other observations:

This activity led to great discussion among participants about pasture condition and also prepared them for what they should be looking for in their own pastures.  The main take away message is pasture management is not a passive activity.  You have to walk pastures and constantly evaluate how they are doing in case you need to adjust management.

Resource: NRCS Guide to Pasture Condition Scoring 

Understanding Your Forage Analysis

If you have ever dealt with Extension folks much, you know we are always suggesting you test something - maybe your soil so you can know what fertilizer to put out or maybe your hay so you can know what you are actually feeding your horse.  So you followed our advise and got your hay tested.  If you used the NC Department of Agriculture lab, then you got a report with a whole bunch of words and numbers on it.  Let's take a really quick look at what some of those numbers mean.  

The first thing I suggest people look at is Dry Matter.  This basically tells you how much water is in the hay.  Too wet and you could have mold issues and even spontaneous combustion.  Too dry and it can be dusty, brittle and you can have leaf loss/shatter.  Remember leaves are typically where most of the nutrition is located.  Ideally hay should be between 10-15% moisture.  Or dry matter should be between 85-90% on the test report.

For the next components, you want to look at the numbers under the Dry Matter Basis column.  This allows you to compare different hays to each other by eliminating the differences in moisture content.  You can compare apples to apples.  Look at the Adjusted Crude Protein component.  This accounts for the amount of crude protein that is actually available to the animal.  Adult horses at maintenance typically need about 10% crude protein.  Horses that are working hard (think a horse in training or a nursing mare) or a yearling will have higher protein needs.  In general, hays with a legume (alfalfa or clover) component will have a higher protein level than a strictly grass hay.

Nitrates can accumulate in hays during stressful times like drought or if too much nitrogen fertilizer was applied.  (not likely for that to happen too often given current fertilizer prices) The general maximum acceptable level for nitrates is 0.5%.  Note that different labs may report nitrates in different ways.

Acid Detergent Fiber (ADF) measures how digestible the hay is.  In other words, how much of the hay can actually be used and utilized by the animal.  The more mature the hay is when it is mowed the lower the digestibility because there is more cellulose and lignin present which is difficult for the equine digestive system to break down.  ADF number below 45 are typically good while numbers above 45 may indicate little nutritional value.

Neutral Detergent Fiber (NDF) is an indication of intake - how much will the horse actually consume.  If the hay is very mature, the animal is not going to want to consume a lot because it is tough and stemmy.  This is a measure of insoluble fiber, cellulose, hemicellulose and lignin.  NDF values under 65 are generally good, while values over 65 may indicate the horses will not eat it.

Digestible energy (DE) is given in a Mcal/pound measurement.  Horses in light work need approximately 20 Mcal of DE per day.

The calcium:phosphorus ratio should be between 1:1 to 3:1 for adult horses at maintenance.

The above information is very general in nature so that you, as a horse owner, can gain a basic understanding of what those number on the forage report mean.  Contact your Extension agent for additional information on forage reports or taking forage samples.  This article did not discuss sugars and non structural carbohydrates, which may be important when feeding horses with metabolic concerns.  Your veterinarian or nutritionist can provide additional assistance for individual horse nutritional needs.

Here are some links to some good articles for additional information.

https://extension.umn.edu/horse-nutrition/understanding-your-hay-analysis#:~:text=Optimum%20horse%20hay%20moisture%20ranges,%3A1%20and%201%3A1.

https://extension.psu.edu/understanding-a-hay-analysis

Are you ready? Hurricane Season is Here!

Hurricane season officially begins on June 1st each year but North Carolina tends to see most of our storms in the next few months.  We may have our homes and families prepared for a hurricane, but it is also important to have a disaster plan for our horses. Below are some tips and reminders from NC State's Extension Specialists Alaina Cross and Mike Yoder.

Before the Storm 

Vaccinations:  All horses should have a tetanus toxoid vaccine within the last year. Due to the increase in mosquitoes after massive rainfall, all horses should also receive West Nile Virus and Eastern/Western Encephalitis vaccines at the beginning of the hurricane season. 

Coggins Test:  A negative Coggins will be necessary if the horse needs to be evacuated to a community shelter or across state lines. 

Health Certificate:  A health certificate is required to cross the state line. This may be necessary if you live in a region that is near the SC/VA borders. A health certificate is valid for 30 days. 

Identification:  Each horse should have at least 2 forms of identification (in case one is lost). Have proof of ownership, including recent photos of the horse including any identifying marks/scars/coloration, ready in the event that you need to claim a loose horse. Examples of possible identifying methods include: 

• A well fitted breakaway halter (a regular halter can trap a horse and possibly strangle them!) with contact information (can be in the form of a luggage tag, a metal ID tag, a zip lock bag secured with duct tape to the halter) 
• A luggage tag with ID braided into the mane or tail (make sure it is water proof). 
• Livestock marker – write your phone number on the horses’s hindquarters with a waterproof livestock marker 
• Microchip 
• ID bands that go around the horse’s neck 

Evacuation Plan:  Hurricanes generally give us at least a day’s notice or two before coming into contact with land. Make sure that you have a written evacuation plan for your horses, especially if you are in a low-lying area, a flood plain, near water, or are near the coast. If you will be in the path of the hurricane, it is highly recommended to evacuate prior to the storm, as transportation with horses when wind gusts are over 40mph is hazardous. Decide at which point you will evacuate (for a category 1, 2, 3, 4, or 5 storm?). Also prioritize NOW which horses will be evacuated in what order if you will have to make more than one trip. 

• Determine two evacuation centers (in opposite directions). For a list of evacuation centers in NC near you, click here: http://www.ncagr.gov/markets/livestock/horse/EquineDisasterResponseAlliancePartners.htm Ensure that your truck and horse trailer are ready for travel (tires in good condition, etc.). 
• Ensure that the vehicle is full of gas. 

Water:  Power loss often occurs with hurricanes, and many horse farms may find that they are unable to provide water to their horses. Each horse sould have 12-20 gallons of water stored per day. Fill all available water troughs. Be creative with your water resources! Line garbage cans and various storage bins or much buckets with plastic contractor bags and fill them with water. Consider a generator to run the well if you have large numbers of horses. Keep chlorine bleach on hand to add to contaminated water if necessary. To purify water, add two drops of chlorine bleach per quart of water and let stand for 30 minutes. 

Feed:  Store a minimum of 72 hours of feed and hay (seven days is best) per horse. It is very possible that roads will be closed because of down power lines and trees and that you will not have access to feed for a period of time after the storm. Cover hay with water proof tarps and store on pallets. Keep grain in water tight containers in the event of flooding. 

Farm Preparation:  Secure all moveable objects. Remove all items from hallways. Secure jumps, lawn furniture, etc. in a secure place. Place all large vehicles/tractors/trailers in an open field where trees cannot fall on them. Turn off electrical power to the barn to avoid any potential fire hazards with power surges or lightning strikes. Secure all gates. Ensure that all emergency tools are working properly and readily available. These include: 

• Chain saw (and fuel!) 
• Hammer/nails 
• Fence repair materials 
• Wire cutters/tool box/pry bar 
• Fire extinguisher
• Duct tape 
• Fuel for generator/tractor 

Emergency First Aid Kit:  Make sure that you have an emergency first aid kit ready and accessible (and waterproof!). Have any medications that a horse will need easily accessible and ensure that you have enough to get you through the storm and the aftermath. Some items that should be included: 

• Bandages (leg wraps and quilts) 
• Antiseptics Scissors/knife 
• Topical antibiotic ointments 
• Tranquilizers 
• Pain relievers (bute, banamine, etc.) 
• Flashlight with extra batteries 
• Extra halters/lead ropes 
• Clean towels 
• Fly spray/swat 

During the Storm 

In or Out?  Should horses be left in the pasture or in the barn? Recommendations from the American Association of Equine Practitioners say that if the pasture has good fencing and limited trees, it is probably best to leave horses outside. Well constructed pole-barns or concrete block barns may provide safety from flying debris, but the horses may become trapped if the wind collapses the building. If you have a sturdy shelter with access to a small, safe paddock, this would be ideal. A horse could escape the building if needed into a safe area. 

• Keep horses out of pastures and areas with electrical lines. If these come down, they can electrocute the animals nearby. 
• Trees with shallow roots will fall easily under hurricane force winds and can injure horses or destroy fencing. 
• Do not keep horses in areas secured by barbed wire, electrical wire, or high tensile wire during a hurricane. 
• Fire ants and snakes will search for high ground during flooding. Keep this in mind when selecting an area to keep your horses if they are to remain in pasture. 
• For NC Animal Disaster Sheltering Resources click here: https://www.ncagr.gov/markets/livestock/horse/EquineDisasterResponseAlliancePartners.htm

After the Storm 

Inspect Animals:  Carefully inspect all horses for injuries, focusing particularly on the eyes and limbs. 

Inspect Property:  Look for down power lines, fence damage, and misc. debris. Take photos of storm damage to present to insurance companies. 

Missing Horse?:  If your horse is missing, contact your local county animal control, sheriff’s department, or local disaster response team. 

Equine Feeds Explained

 

In a perfect world all the horses on a farm, from foals to broodmares to pasture puffs to horses in heavy work, would be fed the same feed out of the same bag. Unfortunately, the nutritional needs of horses vary tremendously based on life stage and workload. Thus, this makes it difficult to design a “one feed fits all.” With that being said, the basis of any equine diet should be forage. Any concentrate (sweet feed, pellet, or grain) and or fortified feed/supplement should compensate for deficiencies in the forage portion of the diet.

Start with feeding a high, quality grass forage (either grass and/or hay) at a minimum of 2% of body weight and expand from there. Just know that a forage-based diet may meet crude protein requirements, but often be deficient in essential amino acids minerals and vitamins. Furthermore, when working with a hard-working performance horse, a forage only diet can also be deficient in a substantial amount of energy. To simplify things, let’s group the main equine feed options into a few categories and discuss recommended feeding rates, human diet comparisons and good candidates for said feeds (extrapolated from Dr. Rachel Mottet, Legacy Equine Nutrition).

Ration Balancer and/or Forage Balancer

·                 Essentially a daily mineral & vitamin supplement often with added protein and/or essential amino acids
·         Minimum feeding rate: 1-2 lb or a few ounces per day
·         Forage balancers with feeding rates of only a few ounces per day do not contain significant protein and may not provide a complete mineral/vitamin package
·         Human food comparison: Daily vitamin & mineral plus a shot of protein and/or amino acids
·         Good candidates: Easy keeper/overweight horses, horses that thrive on forage alone

Complete Feeds

·                    Entire daily food intake including a forage/fiber buffet
·         Hay built into feed (often senior feeds)
·         Minimum feeding rate: 6+ lb per day
·         Option when quality forage is an issue, but $$$
·         Often lower fortification due to higher feeding rates
·         Human food comparison: Your entire daily food intake plus a salad buffet with balanced vitamins, minerals, protein plus roughage in the diet
·         Good candidates: Seniors, horses with compromised dentition or nutritional absorption issues, horses with limited access to quality forage, or alternative option for performance horses

All Around/Performance Feeds

·                 A feed which provides nutrients and fuel to fill in the gaps & to maintain ideal body condition and performance
·         Minimum feeding rate: 4-8 lb per day
·         Varying levels of fortification, starch & sugars
·         Human food comparison: A diet which provides nutrients and fuel needed to maintain normal body condition and/or athletic performance
·         Good candidates: Horses who need more than grass/hay alone; harder working horses

Today’s horse owners might find horse nutrition complicated, but hopefully this explanation of the most common feed categories helps to simplify things. As identifying the nutrients of most concern, the horse’s stage of production, age and/or activity level is critical in determining which is the most appropriate feed for the given situation.