Using Compost vs. Fertilizers on Grasslands: My Personal Experience

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1 Using Compost vs. Fertilizers on Grasslands: My Personal Experience First a bit of history Our Farm is in the Sandhills of mid Moore County with sandy loam soil. We have beef cattle and pleasure riding horses. Our ~10 irrigated acres of pastures were established about 1998, & divided into 8 smaller paddocks which we did rotational grazing. I do annual fall soil testing for each individual paddock and always individualized the fertilizer applications to fit the report recommendations, divided into three (spring/summer/fall) applications, as is recommended. Due to both the increasing cost for fertilizers and my general desire to be more organic & sustainable, I applied a bagged organic fertilizer (Nature Safe) to one pasture in It cost about $30 per bag and because of the low numbers for available N P K on the label I had to use a significant number of bags to deliver the soil testing recommendations per acre. It was quite expensive, but then I only had to apply it once in the spring where I was applying other fertilizer blends to the other 7 pastures 3 times per year/grazing season. I didn t notice any appreciable difference that year, but in March of 2011 that pasture s grass was green, lush and growing rapidly while all the other pastures appeared washed out, pale and not growing yet. That dark green on the left is from organic fertilizer applied a year earlier! Page 1 of 7

2 Clearly the organic fertilizer on the left side had the claimed carry over to the following year as I was observing, but it was so expensive I wondered about using large volume commercially prepared bulk Compost instead and could not find any good information on how well that might work or how to go about doing it. I learned of Brooks Contractors and their Compost available just 20 miles away and inquired about my being a trial/beta site for monitoring use of bulk Compost instead of fertilizer for grasslands. It was decided that I would use BR 1HE, a hotter 6 month old compost blend with higher nutrient analysis at the rate of about 10 tons per acre (approximately two large ~5 ton poultry litter spreaders per acre) in March of I kept two of the 8 pastures as controls, with continued applications of standard bag fertilizers according to the recommendations of the soil testing reports during 2011 and Page 2 of 7

3 The Observations & Results with Documented Soil Test changes: My CEC levels had been stable and averaged about 5.5, which isn t bad, but in the fall testing of 2011 it averaged about 11.0 in the Compost fields and stayed at about 5.5 for the controls with the fertilizer. I doubled up in 2011 applying another 10 tons per acre in the fall and again in March of I had simultaneously begun Strip/Mob grazing with my livestock, subdividing the 8 paddocks into smaller sections with moveable electric fencing so that I had between days of rotation (time before they returned to the same section of grass to graze again) increasing as time went on and the warm season grasses began growing more vigorously. I would have to agree with others who claim that there is a 2 3X increase in the volume/weight of forage eaten when there is a longer time interval until a spot is re grazed. If you haven t switched over to this method then I highly recommend you give it a try! I didn t believe the claims made for it but have to say I wish I d tried it many years sooner since they are mostly true! I stopped feeding supplemental cattle pellets in March 2012 and nutritionally my cattle remain in optimal nutritional form getting all they need from the grazing plus high Mag. Minerals which we keep in front of them near their water sources. Water utilization: The three years, , were well below average rainfall in our area, and I had a 10+ year history of having my irrigation pond run out of water and have to suspend irrigation in August for about 10 years or so. Due to the two previous dry years and the very dry winter of , my irrigation pond began the grazing season of 2012 only half full A very ominous situation and I could imagine how instead of running out in August that it could even be June or July in 2012! Irrigation management dictates that when we get about an inch or more of rain we turn the irrigation system off. It stays off until pastures begin showing signs of wilting and water deficiency when we restart it. We had applied the 10 tons per acre three times (S & F 2011, and spring of 2012). It is claimed that increasing organic matter in the soil just 1% increases water holding capacity in the top foot of soil ~17,000 gal/acre. Long story short, we never ran out of irrigation pond water even starting with half full pond and very little rain, and the pastures looked the best they ve looked during the long hot dry summer in years! Incredible observation, but seeing is believing! This is something I wish we had done years ago! A footnote here: The longer grazing rotation with the taller forage also translates into longer deeper root systems, a well established correlation, which also helps drought proof the forages by having the roots deeper down where water is more prevalent during hot dry spells. This is more due to the grazing methods than directly a result of the Compost, but it is difficult to separate out the importance of each. I believe that both factors are very important and should be practiced by those grazing livestock. Page 3 of 7

4 Forage Re growth after Grazing: I established a systematic rotation for the grazing but due to the two Control pastures which did not have the extra organic matter in their soil to hold moisture/rainfall, nor did the fertilizer seem to meet the nutritional requirements as well so I ended up skipping over those two pastures in the rotations and having to allow them more time to re grow before grazing them again. Just one more reason why compost is better than fertilizer on grasslands! So, what is the plan? After 3 separate applications of 10 tons/acre, I put no additional compost on those pastures. This year, 2013, only the control (previously fertilized) pastures got compost. I had seen enough and could no longer justify keeping them as controls! If you look at the pastures that haven t received any Compost since March 2012, you d think they had been fertilized just a week or two ago they look so green and lush! The claims from the Mob/Strip grazing folks is that the cattle end up doing 24 hour composting of the forage and their studies indicate additional future fertilization is not required, generally. They claim that there are steady increases in soil organic matter and soil nutrient health just due to the Mob Grazing methods. I will continue to do my annual fall soil testing and see for myself what is happening in my own pastures and decide from there. It may be that I just needed the 2 3 initial applications and with the grazing I am doing I may be now on an upward trajectory for soil health and improvement. If there is any indication of decreasing soil nutrient levels or soil organic matter then certainly future additional applications would be planned. Summary: (I am only speaking to my experience over 3 years on my forage pastures.) At most just a single spring application each year is needed. Probably after 2 3 heavy applications one can coast because there is a 3 4 year carry forward of nutrients in the compost that remains in the soil available for future years and crops. I just recommend that you continue annual soil testing to be certain nothing is becoming deficient in the soil nutrients. (Note: watch your ph since BR1 HE has a ph above 7 and I actually got my pasture ph s into the mid 7 s which isn t that desirable for most forages!) Observed Forage growth seems excellent! Eliminates need for expensive supplemental feeds for livestock. I agree that the day rotation ends up producing some 2 3 times the normal amount of consumable livestock forage than one has seen in the past. Clearly those pastures last year that had Compost outperformed the two control pastures (fertilizer applied 3 times during year) when it came to the rate of recovery and re growth, and I want to be very clear about that! Compost s improvement of soil organic matter and the associated increase in water holding capacity is truly remarkable and if nothing else but this were true, it would be worth using Compost! Page 4 of 7

5 If you haven t converted to Mob/strip grazing then learn all about it and get started! It is clearly far superior to even my old 8 pasture rotational grazing! (I personally put them into a new grazing strip 3 times a day which results in more thorough grazing of each area vs. putting them into a larger area for a full day, but obviously takes a bit more time and work.) I look forward to adding to both my documented & observed knowledge in the coming few years and plan to continue to share what I have learned with any who are interested. Mike Rowland c/o The Farm, Carthage, NC mcrowland@embarqmail.com This had been one of my poorest pastures before applying Compost! Note where they just finished grazing before being moved a few minutes before photo taken. Page 5 of 7

6 Addendum (Aug. 30 th, 2013) One other fly in the ointment is that I ve now got heavy growth of Durana clover in almost all areas of my pastures and beginning to become established in my hay field as well. I over seeded some hairy vetch into some pastures (another legume) last fall and was very pleased with the results (adds nitrogen to the pasture plus significant high quality forage in the spring for the animals grazing) so plan to do that this fall to all my grasslands including the hay field. Also, I ll try adding some Birdsfoot trefoil to several pastures to see how it does as well since it s a perennial and with its deep tap root has a significant drought resistance and again is excellent forage for livestock. I find the time and expense of adding the different legumes to the pastures with the No Till drill in the fall is hugely valuable when you consider the cost of nitrogen fertilizer, the much longer effectiveness of the legumes, plus the livestock actually gets to eat the plants adding to the total tons of consumable forage per acre, and likely also enhancing the nutritional value as well since the protein value of the legumes is superior to grass, and more studies are validating the benefits of multiple forage varieties to animal health, not to mention all the blossoms helping the bee population which also benefits from a broader variety of pollen sources to their health as well! They look great too! See clover below! Dung Beetles are another entire chapter! Page 6 of 7

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