Goats eating bark

[Charles Gill]

I am using goats to manage buckthorn at my schools farm and although they have done an excellent job eating the woody shrubs in the hedgerow they have also gone after the bark of the larger trees and nearly girdled all of the trees in their paddock. I don't want to move them until I have a method for dissuading them from this behavior. This is obviously a learned behavior since the woman I borrowed the goats from generally throws whole trees in for them to eat down to the wood, but I was hoping to somehow re-train them to not eat the bark and was looking for suggestions. I think that a home-made pepper spray would work but don't want to hurt the goats. Any ideas? Thanks!

[Peter Smallidge]

Hi Charles:

I ran the Goats in the Woods project with colleagues at Cornell from 1999 through 2003.  We worked to train our goats to strip the bark from sapling trees (mostly beech and striped maple), but to prevent them from damaging the bark of the larger commercial trees.  Goats did a good job of stripping bark (i.e., girdling) the smaller stems.  We didn't have any trouble with the larger trees unless goats were left too long in a paddock. 

For what it's worth, buckthorn is usually considered an invasive species.  It might be a good think if the goats are stripping the bark.

Good luck,

Peter

[Charles Gill]

Hi Peter, Yeah, i know your work, I used your "handbook" to frame my project here at Sterling so thank you for that. The problem I'm having is not that that the goats strip the bark of the buckthorn, that's great, but that they go after the pin cherry trees that make up the canopy. What I'm worried about is, a) they'll kill off the trees and i'll have a lot of poisonous wilted cherry leaves to deal with, b) they'll kill of the trees and the increased sunlight will spur a major growth of buckthorn, bittersweat and burning bush, or c) they'll kill the pin cherry's and any other tree that might be desirable in the stand, i.e. sugar maple, apple and black cherry. 

Right now I'm working on painting the trees with cow manure, the consistency is better than goat manure, to see if that will stop them and hopefully they'll become trained by the time i get to a stand with maples.

Thanks again for your comment and i'll let you know how it turns out.

Charles

[Brett Chedzoy]

Charles,  In my experience with our goats, bark stripping seems to be a combination of two main factors: learned behavior and boredome (too much time spent in one area).  There may be other causes, such as dietary cravings, the attractive palatability of the bark from certain trees, and the utter lack of other food sources.  Short rotations may help, especially if there's an abundance of other good quality forage for the goats to eat.  But if some of the goats seem insistent upon debarking the trees, then you could try training them not to through negative reinforcement.  I recommend visiting Kathy Voth's website: www.livestockforlandscapes.com to read the work that she has done to train animals to eat target species.  The reverse should also work, though you'd have to experiment with the methods to create the negative reinforcement.   

[Maryanne Reynolds]

A Christmas tree farmer has suggested that we paint the trunk of vulnerable trees with white latex paint (paint can be watered down) to keep away goats and deer; the white color is said to be important to keep the sun from absorbing into the tree.  I have no experience with it myself.  Does anyone know of a reason not to try it -- would it hurt the trees?   

[Jeff Jourdain]

I don't think white latex paint will harm the trees.  FEDCO trees in Maine recommends a mixture of white latex interior paint and joint compound for deterring apple borer.  This is from their on line planting guide:

After years of experimentation, I think that painting is the best deterrent. I’ve tried a number of recipes and this is my favorite. It’s easy and requires no hard-to-find ingredients. Mix white interior latex paint with joint compound. (The stuff you smear on sheet rock joints and nail holes—you can buy a small tub at any hardware store. Some exterior paint formulations contain ingredients that can harm the underlying phloem.) The consistency should be thick but still quite easy to paint, not glob on. Repaint periodically or each year as needed. This mix will help deter borers. It will also make for easy detection of any infestation you may have. Look for the frass!

Here's the link:  http://www.fedcoseeds.com/trees/planting_guide.htm#fourteen

 

Maryanne Reynolds said:

A Christmas tree farmer has suggested that we paint the trunk of vulnerable trees with white latex paint (paint can be watered down) to keep away goats and deer; the white color is said to be important to keep the sun from absorbing into the tree.  I have no experience with it myself.  Does anyone know of a reason not to try it -- would it hurt the trees?   

[Joe Orefice]

I agree with Jeff, painting the bark of trees white shouldn't harm the trees. Bill MacKentley at St. Lawrence Nursery has recommended this as well for apple diseases. One of the reasons to avoid dark paints is they may cause hotspots on the bark which can kill the inner cambium (especially on trees with thin bark). It'd be important to ensure that the paint is non-toxic in case the goats decide to give it a try.

Charles, it'd be interesting to hear if you're able to train goats not to eat bark. Depending on how large your stand is you might consider individual fencing around your favorable trees. I've had some luck with polywire simply wrapped around individual planted saplings in my pastures. It is not electrified but my cows know what it looks like and thus avoid it thinking it is electrified - although we all know cows and goats are very different animals. I also suspect with enough time in the area they might figure it out.

The picture below is an example from this summer.  Unfortunately, while it worked for the cows, I'll have to do something more physically preventative when the deer come out in March looking for swollen buds.  Notice the polywire is wrapped right up the stem to the top.

[Joe Orefice]

[Brett Chedzoy]

There are many strategies for protecting trees, and (in my opinion) for an approach to be successful, it has to be skillfully customized to the particular situation.  For example, in Joe's picture above, the (presumably) unelectrified) polywire will deter cattle that have been trained to avoid hot polywire and which are not pressured to go after the young trees by keeping them moving on adequate quality pasture.  The same protection, as Joe points out, would be ineffective against naughty goats, sheep, deer or even cattle that don't respect polywire or which are being pushed too hard and get hungry. 

I haven't tried using repellents to train livestock to avoid high-value trees like the one above in rapid rotational grazing sytems, but after hearing Kathy Voth speak a couple of times last year, I think it could work and probably be the most cost-effective approach.  In other words, teach the grazing animals that "apple trees taste bad".  I suspect that the results (level of success) will vary from operation to operation, depending on numerous variables.

An electrified barrier probably wouldn't be effective in protecting the tree above from small animals unless it was something more complete like a suspended chicken wire cage - which wouldn't be that expensive or difficult to make - but would require dillgent maintenance to make sure it doesn't ground out.

On our farm we've started to experiment with barbed cages made from 2x4 wire mesh about 4' in diameter, where numerous verticals have been cut in half at a sharp 45-degree angle and bent outward to form barbs to prevent animals from rubbing or climbing on the cage.  We recycled the cages from our old orchard, so I don't have an estimated cost/cage.   Young trees inside the cage still need to be protected from rodents and competing vegetation.   Cages are probably a bit pricey (I'm guessing around ~ $10/cage for time and materials) but should be able to be used multiple times over their lifespan.  I don't know yet if these barbs are going to be sufficient, or if something more formidable will be necessary, like wrapping the cage with pigeon barriers (which I'm guessing are pricey). 

A contrasting situation to the one above (a few high-value trees which stand out like magnets) is where there is dense natural regeneration, coppicing or suckering.  In this case, it may still be possible to graze the area and capture some of its feed potential without causing too much harm to the regeneration - but the timing and intensity (duration) of the grazing period is critical.  Ideally, stands of young regeneration would be grazed just prior to leaf-out (early-May in most areas), or just after leaf-drop (mid-October), when grazing animals are more likely to focus on the herbaceous growth and ignore the young trees.  However, depending on the height, density, species composition of regeneration, type of livestock and objectives, some browsing may be acceptable.  I'll close with a picture to illustrate one such example from our farm where we clearcut a black locust stand.  The resulting regeneration (suckering) was too thick, so we've allowed some carefully-timed flash grazing of the goats and cattle over the past few years to thin it out some.  If done right, the taller, better sprouts generally escape browsing, while the lower sprouts get clipped. 

[Brett Chedzoy]