Sub-dividing pastures – advanced paddock grazing
Most horse owners recognise a horse-sick pasture; the one with poor quality grasses containing weeds, compacted, eroded soils and manure build-up with parasite pollution.
Some think the problem is caused by overstocking with too many horses but, did you know that over-grazing and under-grazing are likely to be the biggest issues?
In this article, Certified Permaculture Designer and Equine Nutritionist Mariette van den Berg explains how a well-planned rotational grazing system could turn your horses from pasture destroyers to eco-friendly land managers and genuine soil builders.
The ultimate forager
All horses, domestic or feral, typically display patch-foraging behaviour – in other words, they take a couple of bites out of a plant then move on to the next food patch. This instinctive behaviour is important to their survival for many reasons, for example:
- It allows them to select from a diverse range of plants to meet their nutritional needs.
- They only disturb and foul the ground for a small period of time.
- They avoid eating grasses soiled by their own manure, urine and parasites.
- They move on, giving the grazed or soiled area time to recover over the season.
As responsible horse owners, we should aim to mimic this natural migrating and foraging process as much as we can. One way we can do that is by managing and planning the movement of our horses within our properties.
Plan to succeed
Many horse owners use a rotation system over multiple paddocks, but sometimes the management and rotations are done without an actual plan.
A proper grazing plan using principles like holistic grazing planning or, in permaculture what’s known as ‘advanced cell grazing’, allows you to gain a clearer picture of where the horses need to be and when, and this determines how you plan their moves.
The first step in creating a better grazing plan is to develop a basic understanding of how pasture plants grow and mature, and how you maintain healthy soils.
Second, you need to look at the layout and design of your pasture areas and identify where you could potentially sub-dividing to increase the number of pastures for horses. The more paddocks available, the more moves you can make and the more you can rest your pastures. Of course, paddock size will depend on how much land you have, how many horses you can (or want) to graze together and your own herd dynamics.
Making more paddocks also means more fencing material and you probably want to check what is available, what is safe, keeps the horses in and is reasonably priced.
When planning sub-dividing pastures, you should also consider the ease of moving horses on your property, such as safe laneway systems and gates.
Last and not least, you should also think about how to get water to the animals. Will you have enough water points for each paddock or will you set up a central point system?
Grazing and leaf area management
We hear a lot about ‘over-grazing’, but what does it look like and why is it important?
If grazing animals remove only a small amount of the active green-leaf area, photosynthesis can proceed and the plant can replenish carbohydrate stores, while top and root growth is progressing.
However, if grazing animals remove most of the available leaf area every few days, the plant allocates nearly all growth energy to new leaf growth, the root system diminishes, and less energy is stored (reduced vigour).
Frequent leaf removal without adequate time for the plant to restore its vigour is the physiological basis of over-grazing. Over-grazed pastures produce far below their potential, have a low stand density (how many stands will grow per plant) and poor vigour.
Rest and recovery
The amount of rest that a grazed plant requires to recover its vigour and replenish an effective leaf area is influenced by the period in the growing season and the amount of active leaf area left after being grazed.
A cool-season grass can recover in two to three weeks during its ideal Spring and Autumn growing periods, but may require six weeks or more to recover during the more stressful (hot and dry) months.
Warm-season grasses, on the other hand, grow very slowly during the cool months of Autumn and Winter, but recover quickly following four to six weeks of rest during their ideal Summer growing period.
Regardless of the season, the rest (or recovery) period can be shortened somewhat by leaving a taller leaf area following grazing. This residual leaf area can contribute photosynthesis energy quickly, supplementing stored energy reserves to aid in a much faster recovery.
A reasonable rule of thumb for rapid recovery of pasture plants is:
For cool-season grasses and mixed cool-season grasses and legumes, leave 3 to 4 inches of residual leaf area following grazing.
For warm-season grasses, aim to leave about 4 to 8 inches of leaf area following grazing.
Sub-dividing pastures and advanced paddock grazing
One of the dilemmas we encounter with pasture management is that different grasses recover at different rates so, if you only have a few paddocks (and use long grazing periods), you are likely to over-graze and weaken some plants.
Rapid moves favour the growth of fast growing plants, but the horses return too soon for the slow ones.
Slow moves may expose fast growing plants to a second or third bite without having time to recover. Some plants will be weakened and some may even die.
Partial rest is also damaging, so the best strategy is to extend recovery periods by building the highest possible number of ‘useable’ paddocks or develop a strip grazing system.
Grazing and recovery periods are always linked! So, to minimize the risk of over-grazing, you have to plan the recovery period first.
The desired recovery period and the number of paddocks you have available will dictate what the average grazing period for each paddock should be.
For example: In a property with 6 equal paddocks, a 90-day (3 month) recovery period dictates an average grazing period of 18 days per paddock, i.e. if you move your horses every 18 days, each paddock will get 90 days of rest before it is grazed again.
The calculation is done as follows:
Recovery Period ÷ Number of Paddocks Minus One = Grazing Period
90 ÷ 5 = 18 days of grazing
During rapid growth, the moves could be faster since severely bitten plants might require only a 30 day recovery period. Thus, during the ‘good season’, the average grazing periods for each of the six paddocks would fall to six days.
30 ÷ 5 = 6 days of grazing
The rule of thumb is:
Slow growth = slow moves (and longer recovery period)
Rapid growth = rapid moves (and shorter recovery period)
When in doubt… choose slow moves (See why on next page).
When in doubt, choose slow moves
When in doubt and even though this rule may run counter to instinct, use slow moves. You may be tempted to keep your horses longer on green flushing grass and move them on sooner when it is pale and growing slowly but, as mentioned earlier, fast moves cut days off the recovery time of all paddocks combined and this can damage any slower growing plants and the soil through compaction.
For this reason, in holistic planning, they recommend you plan all moves on a chart. The chart enables you to immediately see the loss of recovery time.
A cell grazing system can be applied to small and large properties to increase pasture availability.
The more you divide your land, the more recovery time each paddock gets. These divisions can be made with portable electric fences.
On small properties and during extended droughts, you may have to adopt additional strategies to maintain grass cover. For example, by designating a ‘sacrifice area’ and providing additional forage.
This sacrifice area will help keep animals off the pastures and buys the grass extra recovery time. Jane Myers’ Equicentral system provides many good solutions that can be implemented on most existing properties (Visit www.equiculture.com.au).
Many horse owners think that over-grazing is caused by stocking density. It is true when the density is high, the impact on a certain area in one day will be great, but if your planning is good, this can actually address many problems and speed up land improvement (it is what happens in natural systems). However, if your planning is sloppy or non-existent, overstocking will dramatically increase the damage you can do to both the land and your animals.
There are many types of fencing systems available that horse owners can choose from and your choice will largely depend on price, safety, aesthetics and ease of maintenance. The safety aspects for avoiding injuries are discussed in detail by Dr Adrian Owen later in following pages of this issue.
While it is important to have permanent boundary fencing, internal fencing can be more flexible. Some people choose a fully flexible design using electric tape, others may use a combination of permanent and electric tape fencing. It will largely depend on the size of your property and the classes of horses you are housing.
When placing fencing, it is important that you consider the landscape and place on contour where possible to reduce erosion problems. This is something we will talk about in a future issue of Horses and People.
Access and water
Access is very important when sub-diving paddocks. We need to be able to move horses safely, consider the shape of the land and allow access for maintenance.
The width of the laneways needs to be considered carefully and will depend on how many horses you want to run together, herd dynamics and the width of machinery that will require access. A reasonable standard is between 4m and 6m.
The access points and type of gates are particularly important when you want to set up central points for loafing and/or water. Gates should fit the specifications of the laneways and pasture access. The type of gate will depend on personal preferences, safety, price and ease of operating.
Clearly, water is an important aspect of your pasture design (you should make sure that horses always have access to clean drinking water). Allowing horses to drink from a dam can cause soil erosion and can be dangerous if they get bogged. It is best to either have a water point in all paddocks or use a central water point system that makes horses move to a specific area to obtain water.
Plan to be flexible
Grazing planning involves constant monitoring of the growth of your grasses and estimating the recovery period accordingly. Once a plan is made or any action taken, you need to monitor what happens from the outset because unforeseen circumstances always lie ahead. When your planning doesn’t work as you expected, you re-plan and continue your monitoring process.
Grazing planning is a dynamic process, but, with time, you will get to know your grasses better, as well as your horses!
View the complete article “Equine Permaculture: Part 2 Sub-Dividing Pastures – Advanced Paddock Grazing” by clicking here
To compliment, read the next part in this series about being a grass farmer.