Cover Crops

(The 14 plant mix of cover crops in front of the Pine Ridge Farm)

This fall, we did something a little different after harvesting our wheat acres, which was putting in a cover crop.  What is a cover crop?  It is a second crop put in towards the end of the growing season to provide ground cover, hold nutrients in the soil, increase organic matter, and reduce compaction.  All of these things should help our primary crop production in the coming years. 

(Look closely and you will see a be on the sunflower)

These all sound like really great things, so implementing a cover crop program seems like it would be easy, obvious, and immediately cost effective, but that isn't the case.  One obstacle is figuring out how to get the crop into the field, and to come up for a good cover before everything freezes up.  Wheat is harvested at the end of June, so we have plenty of time to haul manure and plant the crop before the ground freezes. It is a good place for us to start and see if it works before we start incorporating it into our other crop programs.  We are not quite done harvesting corn for this year, so to put a cover crop into the corn field we would have to fly it on  sometime in August/September.   

(14 plant mix cover crop in September at the Brigham Farm)

Of course we also have to know what to plant.  There are limitless possibilities of what to put in a cover crop mix based on the desired outcomes, climate, etc.  This year we are trying two mixes.  The first is a mix of 14 different varieties, some each of legumes, grasses, brassicas (root vegetables), and broadleaves.  Of course the stars of the show at least visually are the sunflowers, which are covered in bees and butterflies.  The other mix is 2 varieties- oats and tillage radishes- less expensive and less showy, but should get the job done.   

(It's hard to tell how tall the crops are until you are walking around in them)

All of these plants are supposed to winter kill (die off with the frost) but the grasses and roots will hold the nutrients in and keep the ground covered until they fully break down in the spring.  This should give us better nutrient availability from the manure we put on before planting, and better soil to plant into that will hold more moisture through the summer.  If everything goes as it is supposed to, we won't even have to till into the fields in the spring before planting, although right now that seems hard to believe with how tall and hardy our cover crop looks to be.  

 (View of the ground coverage... and a turnip!)

When we tried a cover crop in the past, we had just planted tillage radishes and they were giant (3 feet long and 4-6 inches in diameter), stunk as they decomposed, and we couldn't see any measurable benefit from having them in the field.  That being said, we may have had a yield boost that was subtle, so we aren't quite sure.  This year we worked with some people experienced with cover crops to choose our mixes and planting dates more carefully.  We also planted in a few different fields that aren't our top performers to see if we can make any improvements.  We won't know until next fall how the crops fair, but right now everyone is excited about the potential for improvement and learning new farming practices.

 (Brian displaying our tillage radishes- much smaller than last time!)

PRRS Update: A Year in Review

(Fall morning on the farm- on the right side in the distance you can just make out the hog huts.)

Over the past six months, we have had made big strides in recovery from our PRRS outbreak.  All four of our farrowing farms have been producing PRRS negative (it's a good thing to be negative!) piglets for roughly 4 months now.  This means we have decreased our use of antibiotics to treat secondary infections that arise when the pigs immune systems are compromised from the primary disease.  It's great to see healthy piglets and sows again, and our production through the summer seemed to be better than ever through the summer.  This caused the problem of having too many pigs and not enough space to grow them. We were moving and selling pigs lighter than we usually do, but after the last year it didn't seem like a bad problem to have.  We have continued to vaccinate our sows every 3 months for PRRS with a different vaccine or serum each time, so our strain is less likely to mutate into a new strain and cause massive losses again.

Since we have negative piglets being born, you would think that everything is healthy and disease free, but that is not yet the case.  When recovering from this type of disease, everything is done in stages. With the farrowing farms appearing to be clean and stable we now have to empty and clean all of our nurseries, and then all of our finishers.  Right now we are working through each nursery, getting it completely empty, washing, and then letting it sit empty for a few days before loading with new pigs.  Prior to all of the farrowing farms producing negative pigs, we had to mix sick pigs with clean ones, so the clean ones would also get sick.  It wasn't something we wanted to do, but there weren't many options.  Once we had all negative pigs coming to the nurseries, the older pigs in the nursery would spread the sickness to the younger ones who hadn't been exposed and cause more loss.  By emptying and cleaning each barn, we hope to break the cycle.

Another problem that has developed in the finishers are an outbreak of Circo Virus.  Since our older pigs have a compromised immune system, they are susecptible to secondary infection.  Circo Virus is a disease that has been present in our herd for a number of years, but is usually controlled by a vaccine we give to pigs just before they are weaned.  This would be similar to how the measles or chicken pox are now controlled in the human population.  Now we think we are seeing the Circo flare-up due to PRRS immune suppression, so we are giving a booster shot of Circo vaccine to pigs   before they leave the nursery.  We just started this last week, so we are vaccinating a lot of pigs in a short period of time, trying to save them from sickness as they get older.  Once the Circo Virus develops clinical signs, there isn't a whole lot we can do to help the pigs, so vaccination is the best we can do to raise a healthy herd.

At this point, the pigs are recovering better than expected by our vet, even though it feels slow to all of us on the farm.  We have had setbacks due to secondary infection, but as of yet we haven't seen any re-break from PRRS, and if we can keep it that way we will continue to work towards becoming PRRS naive once again.  The difference between negative and naive is that when we have a negative herd we will still vaccinate for the PRRS virus, but once we go naive we will stop vaccinations and see if the pigs stay disease free.  Not only does this save us money, but it will also mean we have eliminated the virus from our herd, as small pox has been eliminated from human populations. Anytime you can eliminate a deadly disease it is a victory.