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Goats per acre: a guide vs. rule

There are so many natural, biological factors that come into play when grazing goats. This is the main reason the goats per acre calculation should be used as a guide. It’s really about the context of your farm or ranch, which impacts how many goats the land can handle.

Factors impacting how many acres of land is needed

The goats per acre calculation is very dependent on your particular area and various factors will impact how many goats your land can handle long term, including:

• Your region’s weather conditions, including annual rainfall and your rainy season
• Forage availability seasonally and year-round from your pastures
• Quality of forage throughout the growing season
• Type of forage available: brush, grass, alfalfa, traditional pasture, wooded areas, etc.
• Length of time in a paddock (continuous grazing vs rotational grazing)
• Soil quality: The health of your soil will impact how productive it is in producing pasture and feed for your goats. With each grazing season, you’ll find your productivity and production of forage will increase as your soil quality increases each year. Managed, rotational grazing will help build and improve your soil quality year over year
• Breed of goats: Meat goat breeds, such as Kiko or Spanish goats may do a better job utilizing and thriving on pasture alone than a Boer goat due to heartiness or even many dairy goat breeds since they require supplemental feed

Related Terminology

First, let’s review the terminology related to rotational grazing and calculating how many goats per acre.

• Stocking Rates: The technical term for how many goats per acre or how much space or how much land your goats might need
• Acre of Land: An acre of land is a measurement for land in the U.S. It is the equivalent to 43,560 square feet 
• Grazing Season: The time period when you’re grazing your goats during a year
• Average Pasture Yield: How much on average your pasture yields for useable forage as feed for your goats
• Paddocks: A smaller section of your pasture
• Rotational Grazing: Moving goats every few days from one paddock of the pasture to another paddock. This helps increase pasture productivity and is good for the health of your soil and goats as is reduces issues with internal parasites. This is also sometimes referred to as a rotational grazing system. 
• Continuous Grazing: Putting your goats in a pasture for the entire grazing season and not using paddocks. Continuous access to the same pasture will greatly reduce the productivity of your pastures and increase the chances of having internal parasite issues with your goats.
• Animal Unit: Some stocking rate calculations may reference animal units. This is not referring to the actual number of animals or goats you’re raising, but the weight mass based on “one animal unit” that is 1,000 lbs., based off the live weight of a cow and calf. An animal unit for a goat with two kids (170 lb. as an example) would be roughly 5.8 goats.  

How to calculate goats per acre

The stocking rate for goats, or the goats per acre, calculation is a conservative average over the seasonality of a year. Actual numbers will vary from pastures to pasture and region to region due to variability with your pasture condition, type of soil, weather, and your pasture management practices with grazing (rotational grazing vs. continuous).

Specific information needed to make the calculation

Here’s the information you’ll need to determine your space requirements and number of acres of pasture you’ll need for your goats:

• Estimated average pasture yield per acre. This varies based different forage mixes. See the next section on finding your average pasture yield per acre
• Estimated grazing season in days. For example, in Wisconsin an average grazing season might be May 15-October 31, which is 168 days. This is based on the growing season for your pastures. If you plan to stockpile your pastures for an extended grazing season you can include this in your grazing season days. In many cases it is very normal to not graze the entire year due to climate factors.
• Estimated average weight of your goats for the season. Average: 170 lb. this is based on one doe/female goat (90 lb.) with a set of kids (40 lb. each). This also can be calculated this way: (weight at start of grazing season + weight at end of grazing season) / 2

Finding your average pasture yield per acre

Here’s how to find your average pasture yield per acre: 

• Visit the USDA NRCS Web Soil Survey website to determine your farm or ranch soil types. YThis is really valuable tool that just requires a little bit of time on your end to access the soil maps online for your land. You can learn more about how to do that in this blog article.
• Then, search for Forage Suitability Groups documents based on your dominant soil types. Be sure to write down the corresponding number/code so you can search for this document.
• Go to the USDA NRCS eFotog site and search by your state -> Natural and Cultural Resource Information -> Forage Suitability Groups -> Look by County. If you can’t find your FSG document number look in a neighboring county, or try Googling the number with the term Forage Suitability Group. If you still can’t find it, reach out to your county NRCS conservationist or office (local service center) for their help in accessing these documents.
• In the Forage Suitability Group document, select your dominant plant species. Based on an estimated ratio, calculate out your estimated average pasture yield based on the grazing management intensity (low: continuous grazing or high: rotational grazing). If you’re just starting out, you may want to take an average of these two grazing approaches. Remember the goats per acre calculation is to serve as a guide, so making an estimate of your pasture yields is just that. An estimate. Don’t get hung up on getting it just right. Do you have native pasture? How to assess this
• Each Forage Suitability Group will have a listing of plant common plant species based on your soil types with production yield estimates

If you find that your land as soils with different needs, or certain areas greatly differ, then create separate goats per acre calculations for each area based on those soil types and forage suitability groups.

Goats per Acre Calculation

Note the 0.04 is is used since goats and other ruminants need to have access to 4% of their live weight in forage (2.5% intake, 0.5% trampling loss, 1% buffer). The 0.04 can decrease if you’re feeding your goats hay or grain as a supplement during times when your pastures aren’t producing as much forage.

Goats per acre calculator

I have a free a Goats per Acre Calculator you can download through the link below. It’s easy to use and just add specific information for your farm or ranch to determine how many goats your land could handle.

Using good pasture management practices

Once you know how many goats per acre your land can handle, your work isn’t done. First, the calculation is based on a rotational grazing system, not a continuous grazing system.

This means you can’t just put your goats out on your 20 acres and leave them there all summer. That is going to end in a lot of problems, including ruining and depleting the quality of your pasture and soil health, lead to internal parasite issues with your goats, and even tempt your goats to want to be “escape artists” to find a better source of food once they’ve eaten all the good stuff in your pasture.

So how do you implement good pasture management practices once you know your goats per acre numbers? Here’s how to do just that:

1. Train your goats to electric fence so they learn to respect it right from the start
2. Fence off your land into small paddocks (sections of land) with portable electric fencing.
3. Move your goats every 1-2 days to a new paddock based on how much they’ve eaten and what’s left for forage. You still want to have standing grass, at least 3-4 inches. A good measure is have the goats eat half and leave half based on when they first entered the paddock. This will make it easier for the plants to regrow quicker. If they are eaten down to the ground it will delay the regrowth and expose the soil. When goats are grazing, they shed parasite eggs in their manure throughout the pasture. Research has shown that parasites will become infective after 3-4 days of hatching (Zajac, A. 2013)
4. Keep moving your goats to new paddocks. They shouldn’t return to a spot any earlier than 45 days, if not longer. This allows for the parasite cycle to end, as well as the pasture to regrowth. 

What we do on our farm

We move our goat herd every 1-2 days to a new paddock and don’t return to a paddock any sooner than 45 days. This next grazing season I am planning to have longer rest periods, moving closer to 60 days. This should continue to reduce parasite issues, as well as improve the over all quality of our pastures with regrowth of grasses, legumes and forbs, as well as contribute to the improvement of soil health.

From there my approach to managing our goats per acre on pasture includes:

• Basing moves off forage availability: are they eating everything or being selective? Too selective might mean the paddock might be a bit oversized. I like the principle of take half, leave half.
• Assessing visual indicators of when to move/paddock sizing
• Our paddocks tend to be about an acre in our pastures. We’re grazing about 100 head of goats/sheep with kids/lambs on 100 acres of our farm, which includes permanent pasture, hayfields and an old oak savanna we are restoring.
• This is what works with our setup and forage availability, it will be different based on others forage availability different regions. For us we find alot of variability between our woods and pasture, as well as seasonality (spring flush, summer slump and fall regrowth in our pastures).

References: 

Undersander, D., Albert, B., Cosgrove, D., Johnson, D., and Peterson, P. Pastures for Profile: A Guide to Rotational Grazing. 2014. University of Wisconsin-Madison. Accessed at https://learningstore.extension.wisc.edu/products/pastures-for-profit-a-guide-to-rotational-grazing-p96

Zajac, A. 2013. Biology of parasites. In: Proceedings of American Consortium of Parasite Control Tenth Anniversary Conference. American Consortium for Small Ruminant Parasite Control, Fort Valley, Georgia. Available at https://wormx.info/2013-conference

Related blog posts

• Goat Fencing Requirements and Options
• What Sustainability Looks Like on this Wisconsin Goat Farm (podcast)
• How to use a Soil Map for Your Pastures
• All About Goat Pasture