Final Report for FNC01-371
Chris Chmiel of Albany, Ohio received a SARE grant in September of 2001 to develop techniques that would allow grazing animals to be used in pawpaw patches for brush management and organic fertilization.
He provided information about his project to others through a brochure, which is included in this report, a demonstration at a local grazers council field day in spring 2002, and educational workshops on his project at the Ohio Pawpaw Festival 2003 and 2004. (For more information on the festival, visit the website: www.ohiopawpaw.org.) Chmiel also gave talks on pawpaws at a variety of events. He is a board member of The Paw Paw Foundation.
For his grant project, Chmiel planted pawpaw seedlings around the edges of the fields at two local cow dairies and one beef cattle operation. He also worked with a local dairyman who had established pawpaws and a herd of five goats. On this farm, high tensile fence lines were established to encourage the goats to graze in the pawpaw patches.
The pawpaw patches that received some care and were planted on better soils had the best success rate. Patches that were left on their own did not thrive. Chmiel notes,"Mulch and drip irrigation also helped with seedling establishment. Trees can be staked and protected with tree tubes, unfortunately this does attract most animals to use them as rubbing posts. Often times they get broken, especially if there is a high stocking ratio. Plantings right along the permanent fence lines did better than plantings inside the pasture along the paddock temorary fences."
Chmiel says, "Established pawpaw patches, if fenced properly for the appropriate animal, can easily be managed by grazing animals. The problem for us in this experiment was having the appropriate fence for the appropriate animal." Goats seemed to work the best of all of the animals, but Chmiel explains that they also require the largest investment for fencing.
The stocking rate is also important. Chmiel explains, "If I did this project again, I'd try and have more goats and more fencing in place to really maximize the advantages of this system." He did not have enough goats to do all the grazing work that was needed in the established pawpaw patches.
Chmiel remains enthusiastic about managing pawpaw patches with grazing animals. He says, "Using pawpaws in a silvopastoral system as compared to a conventional orchard system makes sense for many reasons." These include: efficient grass and brush management (taking advantage of the natural chemicals in pawpaws that help keep animals from grazing on them), having an animal crop to harvest while waiting for the pawpaw crop to develop, promoting organic production and tree health by fertilizing with manure, increasing pollination (pawpaws are pollinated by flies and the manure attracts flies, which may help increase pollination), and reducing the amount of mowing required, which Chmiel points out "is very time consuming, costly and dangerous in hilly areas."
Chmiel says, "I expected this system to work because it was already happening naturally on farms all over my local area. These pawpaw patches in and around pastures were all producing beautiful and bountiful pawpaws. I just did some work making the patches more accessible. The part I didn't expect was how challenging it would be to get traditional animal farmers to think about the pawpaw as a money making crop."
He notes, " The biggest thing I'm still learning from this grant is that currently in my local agricultural region, silvopastoralism is virtually non-existent. No one seems to be using animals to manage for an additional tree crop. The rotational grazing movement is strongest with cow, horse and sheep farms which manage grass, but rarely do these farms harvest more than black locust fence posts, firewood or timber. The fruit and nut crops that are possible, like pawpaws, black walnuts and others are not being incorporated into the farms. The less highly managed pastures lend themselves to letting wild pawpaws thrive, but the farmers don't seem to value the pawpaw crop as a cash crop.
"This realization, that there are few local silvopastoral examples for me has driven me to search for examples from other areas in America and the world. It makes me realize that even though something isn't being practiced locally, doesn't mean it couldn't be or shouldn't be.
"Overall, this grant project has affected my operation by helping me focus on goats. Goats are ideal for young pawpaw orchards. They tend not to trample small pawpaw trees like the larger cows or horses. Goats are also ideal for the steep hills and brush that characterize my farm and the local area in general."
Chmiel believes this production model -- using animals to manage pawpaw patches -- will ultimately become the standard for organic pawpaw production in America. He will continue to promote growing organic pawpaws to other farmers because of the many benefits this system offers.
As a part of his project, Chris Chmiel produced the following brochure and published it in June 2002.
Using Animals To Manage Pawpaw Patches
Grazing animals will not eat the pawpaw tree, including its leaves, bark and unripe fruit. Learn techniques that integrate animal grazing successfully into organic pawpaw patch and orchard management.
Why animals don't graze on the pawpaw tree
Scientists are finding that the pawpaw tree (Asimina triloba), North America's largest native fruit tree, is also full of potent chemicals that can be used as medicines and natural pesticides. These same chemicals, coined Annonaceous acetogenins by Dr. Jerry McGlaughlin are strong enough to keep all grazing animals from eating the pawpaw leaves, bark and unripe fruit. Goats, sheep, horses, deer, and cattle will not damage the pawpaw tree significantly by browsing.
These animals WILL damage a tree by running it over, bending it over to eat some other plant or rubbing on it. Pawpaw trees are extremely fragile and can easily be broken and damaged by a herd of animals. Taller and thicker trees are less prone to damage by grazing animals. Young, small seedlings are very susceptible to being trampled or damaged in one way or another.
Use small animals with small trees
If you're just planting an orchard and have small trees, you may want to focus on sheep and goats. These smaller animals don't weigh that much and have a lot less impact on small trees. The animals may wind up stepping on a tree, especially if there is a high animal stocking ratio. Sheep and goats are great for keeping grass and brush down in pawpaw orchards and patches. They also leave behind fertility in the form of urine and manure to help fertilize the nitrogen hungry pawpaw trees.
Larger trees can handle larger animals
As the pawpaw trees grow in size and stature, they can accommodate larger grazing animals like cattle, horses, llamas and others. The unfortunate thing about larger pawpaw trees is that they make picking a lot harder. Many pawpaw growers would like to have their trees short enough to pick by hand or with a pawpaw picker. You can keep your trees short by pruning out the central leader or by bending the tree over so that it grows at an angle, making picking extremely easy. Animals simply moving through the trees may knock off low hanging fruit though.
Pawpaws along the fence lines
Pawpaws usually produce pretty well along a fence or hedgerow of a pasture. The pawpaw enjoys the additional sunlight from the pasture. The cleared pasture also makes it really easy to get to the pawpaws during the harvest season. As the pawpaw patch matures, more and more runners will begin to grow out into the pasture. These sprouts are excellent for use as rootstock for grafting developed or select pawpaw varieties on to. These additional varieties will help insure that there is plenty of cross-pollination occurring in the patch. These smaller suckers can easily be fenced off with small pieces of poly-wire in an electrical fencing system, since they are close to the fence.
Pawpaw flowers are primarily fly pollinated
Pawpaw flowers are a dark red color and downward opening flowers. They aren’t designed to attract bees, but rather flies. The flowers begin opening in the early spring before the leaves have started to break bud. Depending on the spring conditions, there may or may not be a lot of insect activity. Continuous cold and rainy conditions can hamper the insect activity. Putting animals in the pawpaw patch during flower set may help increase the number of flies and thusly increasing the chance of pollination. Some growers even go so far as hanging buckets of road kill in their trees during flower set to increase pollination.
Yearly schedule for Using Animals to Manage Pawpaw Patches
Winter: Pawpaw trees love nitrogen, so winter feeding in or close to the pawpaw patches can help build the organic matter in the soil. The hay that is wasted after feedings and manure that is deposited during the winter months helps build soil fertility for later in the year.
Spring: Graze your animals in the pawpaw patch during the early spring just before and during the time pawpaw flowers are open. This may help with pollination. They will also help eat up that first new grass and brush, keeping the patch accessible and fertilized.
As the flowers disappear and leaf growth starts this begins the grafting season and most likely you will NOT want animals in the pawpaws at this time. Grafts are fragile until several years old, but they are extremely fragile right when they are done. By grafting on branches or trunks higher than your animals, you may be able to avoid all possible damage.
Summer: This is a good time to get your animals back into the patch grazing. They will help graze down the competition that might start taking off in the patch, like the multiflora rose, Japanese honeysuckle and other brushy, viney species. This helps keep the patch accessible.
Since the summer is the most important time to fertilize the pawpaws, this is also an excellent time to get the herd to deposit manure and urine in the patch. If they can get out of the hot summer sun in the pawpaws they may enjoy the shade as well. Don’t worry about the animals grazing on the unripe pawpaws. All it takes is one nibble of the unripe fruit and animals will quickly realize that they don’t want to eat it.
Fall: Time to fence your herd out of the pawpaw patch. Most mammals like to eat pawpaw fruit when they are ripe. So this is exactly the time you don’t want your herd in the pawpaws eating your fruit. You probably don’t want fresh manure underneath your pawpaw trees at this time either. When the fruit is all gone, continue to rotate the herd in the patch.
More about the pawpaw biomass
The acetogenins that are harvested from the pawpaw biomass are the highest in May to mid-June when the sap is flowing. This is the time of year to harvest pawpaw medicinal biomass. The leaves, seeds, unripe fruit, twigs and bark all contain these powerful acetogenins.
Currently the pawpaw twigs of a ½” in diameter or smaller are harvested for the medicinal content. If larger pieces of pawpaw are taken, the bark must be stripped. The bark is more potent than the wood. It can be easily peeled away from the wood as long as it is done in a timely fashion. If the wood and bark is allowed to dry out, the stripping is almost impossible.
Integration Acres Ltd.
160 Cherry Ridge Rd.
Albany, OH 45710
Integration Acres Ltd. is a small and growing company dedicated to providing high quality biologically diverse products in a sustainable manner. Pawpaw trees, seeds, fruit, fruit products, pickers, tours and management are all available.
Partial funding for the work reported here was provided by a grant from the USDA Sustainable Agriculture Research and Education (SARE) Program.