Your hay storage needs to balance storage cost and forage loss.
Given the value of hay today, the economic loss from large round bales stored outside, without cover, on the ground can be excessive. This spring, premium-quality alfalfa hay sold for $250 to $300 per ton, good-quality alfalfa was $130 to $270 per ton and the basic production cost for nitrogen-fertilized grass hay was $120.
If there is only a 10 percent loss of dry matter during storage, this amounts to $12 to $30 per ton or $6 to $15 per 1,000-pound bale (see table).
Damage to large round bales stored outside occurs from rain soaking into the top and sides of the bales and moisture wicking up from the soil into the bottom of the bales. When large round bales are stored outside, storage losses are affected by a number of variables:
1. Bale size — large diameter bales have less surface per ton of hay than small bales.
2. Bale density — tight bales shed water better than loose bales.
3. Type and number of wraps on bale — more twine or net wraps improve water shedding.
4. Hay type — grass makes better thatch than legume.
5. Soil drainage — well-drained hilltop or gravel soil allows less bottom spoilage than low areas or loam or clay-type soil.
6. Weather — dry weather results in low storage loss; frequent rain or wet snow mean a high loss.
7. Bale orientation — north-south rows are better than east-west rows for the sun drying bales between rains.
8. Bale spacing — bales far enough apart to allow good air circulation and prevent deep snow from drifting up between and on bales.
9. Bale location — exposed to sun and wind to dry bales between rains versus under trees.
10. Length of storage — one season less loss than two seasons.
Considerable research has been conducted on round bale storage under different management scenarios. Bales stored directly on the ground and uncovered fare the worst, with 10 to 25 percent losses reported most. Storage loss ranged from 5 to 61 percent under these storage conditions.
Providing some cover
There a number of practical storage options that are an improvement over uncovered storage on the ground such as:
• Covered bales on the ground • Uncovered bales on a gravel pad • Covered bales on a gravel pad • Bales stored in a low-cost hoop barn with a gravel floor When making an economic comparison of alternatives, local costs are the only ones that matter. These include the cost of materials, hired or on-farm labor to erect a barn or manage tarps, taxes, and the cost for buying and hauling gravel.
Here is a quick comparison of two alternatives. A hoop barn 40 feet wide by 60 feet long with a 15- year warranty can be purchased for $6,500 to $13,500, depending on snowload strength required. Adding $3,500 for site development and gravel and $4,000 for sweat equity or cash to a contractor brings this to $14,000 to $21,000 to store 270 bales or $3.45 to $5.19 per bale per year.
This represents only 6 to 9 percent of the value of $120 per ton hay. A 23- by 48-foot tarp with a 5-year warranty, heavy tubing for the side pockets and tie-down anchors costs $630 for 72 bales. A gravel pad may add $400. This comes to $2.86 per bale per year or 5 percent of the value of $120 per ton hay.
Either of these options, at these costs, are an improvement over storing hay uncovered on the ground.
Each option has its advantages and disadvantages. The hoop barn is easy and convenient to use but may cause a rise in taxes.
Tarps have a low initial cost and quick payback time but have a short life and require more annual labor. Without the gravel pad, a tarp can be relocated from year to year as needed. All alternatives need to be compared based on your local costs, the forage losses occurring under current conditions and expected losses under improved management, the local value of the hay, and the value of time for labor and management of the storage system.
Given the cost of storage alternatives and the value of hay crops, now is a good time to look at optimizing your hay storage system.