Wood to Feed Program Gets Most Out of Juniper Trees
By Heather Smith Thomas
December 1, 2013) An innovative project in Texas has found a beneficial use for juniper trees that degrade range and pastures. With the rising cost of livestock feed and the cost of removing juniper, the goal of this project is to convert these woody plants into low-cost feed.
Travis Whitney, Ph.D., at Texas AgriLife Research, San Angelo, started by looking at feeding juniper leaves to sheep and goats as a nutritional roughage source, and then began a study on feeding the entire tree.
When he came to San Angelo in 2005 to do research in sheep and goat nutrition, he looked through studies done by his predecessors. “The reason this research center is located here is primarily because of sheep and goats. My predecessors have done a lot of research how to supplement goats and sheep to increase their consumption of juniper leaves, to help reduce the infestation of these trees in pastures,” says Whitney.
“Through their research I knew goats would consume up to about 33 percent of their diet as fresh juniper leaves, especially during winter,” he says. “Ed Houston, a nutritionist here, had plucked juniper leaves during the 1980s and looked at these in terms of digestibility, crude protein, fiber and nutritional quality.
“Knowing that sheep and goats would eat the leaves, I wondered if it could be economically viable for ranchers to cut down trees, let the trees dry, shake the trees and use the leaves,” Whitney adds.
Nutrition and Digestion
“The leaves themselves are about 65 percent digested, which is very close to alfalfa. The leaves are between 6 percent and 7.5 percent protein,” says Whitney. The neutral detergent fiber in mature redberry juniper trees (the whole ground-up tree) is about 66 percent and acid detergent fiber about 56 percent.
“The fiber content is lower compared to cottonseed hulls, often used as a roughage source. Cottonseed hulls are 21 percent to 28 percent digested with 5 percent to 6.5 percent crude protein, 80 percent neutral detergent fiber and 70 percent acid detergent fiber. Neutral detergent fiber is an indicator of intake. Acid detergent fiber is correlated to digestibility,” says Whitney.
“When we did our study with the leaves we replaced cottonseed hulls in growing lamb diets with various amounts of juniper leaves. We found that when we replaced all the cottonseed hulls with juniper leaves the lambs performed similarly, but they actually did better when we only replaced half the cottonseed hulls – because digestibility of the juniper leaves is so high that they didn’t make a very good roughage source,” he explains.
“The leaves made a pretty good energy source. We fed it at 30 percent of the diet for the first 28 days of our study and at 10 percent until the end (replacing all the cottonseed hulls). Those lambs performed very well, comparable to the controls.”
As they got farther into their study, the labor costs of getting the leaves off the trees more than offset the advantages.
“It’s like getting the needles from a dry Christmas tree. Then we started lopping off the limbs and grinding them up with the leaves, to make a good roughage source. We used the smaller limbs that were less than 2 inches in diameter. We chipped that material, blowing it into a peanut-drying trailer and let it dry about four hours. In that length of time it goes from about 60- percent dry matter to about 92- percent dry matter. We put that dried material into a hammermill to reduce it to small particles, putting it through a 4.75 millimeter screen (nearly 3/16 inch) to make a feed product,” he explains.
The limbs are chopped from the green tree rather than having to dry them.
In one of the studies using this product they fed lambs again in a feedlot situation and gradually replaced the oat hay in the mixed diet.
“We compared four treatments, replacing none of the oat hay, 33 percent of the oat hay, 66 percent of the oat hay or all the oat hay with ground juniper. When we replaced all the oat hay with ground juniper, those lambs’ growth performance and efficiency were the same as the lambs on 100 percent oat hay,” says Whitney.
“When we replaced either 33 percent or 66 percent of the oat hay, the lambs actually did better than the ones on just oat hay. I think the additional fiber in the juniper may help the rumen environment, altering rumen bacteria and increasing digestibility efficiency. All of these diets included 40 percent dried distillers grains, which contain a lot of highly digestible fiber. The lignin in the juniper wood may be complementing this,” he says.
Harvesting Whole Trees
Now he’s working with another trial, harvesting the whole trees and not just the limbs.
“We are trying to expand this work to other juniper species to make it applicable in more regions. We’ve done a research project comparing red berry juniper to blue berry juniper, one-seed juniper (prevalent in New Mexico) and eastern red cedar (prevalent from central Texas to all eastern states). Eastern red cedar is a huge problem, taking over many pastures. It contains different terpene profiles and grows more looks like a pine tree than the other juniperus species,” says Whitney.
“I thought the eastern red cedar would have higher lignin and be less digestible because it’s such a big tree. However, it was 29- percent digestible. Looking at cottonseed hulls there are a few reports showing up to 30- percent digested, but in the batches we used, we found them about 20- percent to 23- percent digested. So when grinding up the whole tree juniper tree and finding that it’s more digestible than cottonseed hulls, this is incredible,” he says.
Crude protein in mature trees was 3.5 percent to 3.6 percent. When they looked at smaller trees, less than 6 feet tall, their feed quality increased to almost 4.7 percent crude protein. Fiber went down significantly and digestibility jumped up. Immature red berry trees were 50- percent digestible, blue berry about 44 percent, the one-seed about 50 percent and the eastern red cedar 33 percent.
Harvesting Juniper for Food
“We are working with Cedar Beetle (Concan, Texas), a company that has been commercially removing brush from properties for the past 50 years,” says Whitney. “This company and several other outfits who grind brush and make mulch and chips have shown interest in our Wood to Feed Program. Economic estimates show that trees can be harvested, chipped, hammermilled and sold profitably at $130 per dry ton. This is comparable to cottonseed hulls and much cheaper than hay.”
To assess market potential, Whitney looked at the number of cattle, sheep and goats on feed in Texas and estimated the amount of roughage they would consume, days on feed, etc.
“If even just 25 percent of the traditional roughage sources currently fed was to be replaced with ground juniper, more than 433,000 tons of ground juniper or mesquite would be needed each year, as a rough estimate,” says Whitney.
This is a huge potential. If there is value in the product, commercial tree harvesters could remove – for free – about 4.2 million trees per year. The positive effects on natural resources, improving range and pastures, water tables, etc. would be huge. Another option, on a smaller scale, might be for individual companies to hand harvest juniper trees. The rancher could back a trailer up to the site so the material could be blown right into the trailer.
“If livestock producers had access to those chips, all they need to do is hammermill and mix it to create an economical feed source,” says Whitney.
“The most inefficient way would probably be to drive from San Angelo to Austin with just a truck and trailer that hauls 10,000 pounds of chips, blown into the back of the trailer,” he says. “With labor, cost of maintenance, etc. a rough estimate would be a cost of $20 to $25 per ton after it was hammermilled. Even if it cost $75 per ton, that’s still a lot cheaper than buying any other roughage source right now. There are many little niche places where it could enter the feed market,” he adds.
Acceptance as a Feed Product
The next step is to get juniper approved as a feed ingredient. All feed ingredients have to be approved through the Food and Drug Administration or be listed with the Association of American Feed Control Officials in order to be sold commercially.
“Once we get it approved as a feed source (and I think we can, because ground aspen trees have been approved) I’m hoping that this will become a commercial feed source,” he says.
“If it becomes a feed ingredient, it can be shipped in bulk in rail cars and sold to local feed mills, just as they would use cottonseed hulls or ground hay. When this product is hammermilled it actually flows much better than ground hay or cottonseed hulls and will be easier to handle,” Whitney says.
He is working on a grant to help producers form a co-op.
“We’ve done some surveys with sheep and goat producers and they are very interested. It would probably work best to have a centralized location and cooperating producers would buy into this and have access to big chippers and necessary equipment,” he says.
Whitney is hoping to get juniper approved as a feed ingredient within a year. It’s been a rewarding project to take something that is detrimental to pastures and make something useful from it.
Whitney hopes to have a Wood to Feed website soon.
“Producers can discuss ways they are doing it on their own property and we can update them on what we are doing. Our team consists of range specialists, water specialists, economists, meat and fiber specialists, parasitologists, rumen physiologists and bacteriologists,” he says.
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