Growing Beef Newsletter
July 2026, Volume 17, Issue 1
How to determine which fields to stockpile
Shelby Gruss, ISU Extension forage specialist
Stockpiling is the practice of allowing forage, whether pasture or hay ground, to accumulate growth at the end of the growing season. The goal is to graze after a killing freeze when the forage goes dormant. It is most commonly employed with perennial forage species, which typically require 60-80 days of growth prior to a killing freeze to store enough biomass for winter grazing. One of the central challenges of the system is identifying and setting aside sufficient acres in late summer, acres that would otherwise be grazed, to support winter feed needs. Choosing the right fields is as important as the agronomic management that follows.
Consider your totation and grazing system
The first question to ask when selecting stockpile fields is: where are you in your rotation? Fields that are scheduled to be grazed in early fall are poor candidates for stockpiling, as they will be entered before adequate growth accumulates. Fields that are coming off a summer rest period or that you can afford to defer from late-July or mid- August through the killing freeze are your best options.
Think through how many days you are rotating across your system. If you are running a 30-day rotation and have 10 paddocks, you have built-in flexibility; if your rotation is tighter, dedicating fields to stockpile will require intentional planning to avoid overgrazing the remaining paddocks. The goal is to identify fields you can genuinely afford to exclude from the fall rotation without compromising the rest of your herd's forage access.
Assess your total forage inventory
Before committing acres to stockpile, take stock of your overall forage situation. How much hay do you have in storage? What is your crop residue availability? Stockpiling is most valuable as part of a layered winter grazing strategy, not as a standalone solution. Producers who have adequate hay reserves can afford to be more aggressive in setting aside stockpile acres; those who are tight on stored feed may need to balance stockpile goals against current herd needs.
A useful approach is to graze crop residue first after the killing freeze, then move to stockpiled forages, and reserve hay for the periods when quality and quantity of grazed forage are insufficient. This sequencing maximizes the value of each feed source and extends the grazing season as long as possible. Research supports the economic case for this approach - a 2019 North Carolina study estimated that grazing stockpiled forages saved approximately $1.28 per cow per day compared to feeding hay. An Iowa study comparing winter grazing strategies found that stockpile and crop residue systems extended grazing days from 57 to 85 days and reduced stored feed use by 1,382 to 2,356 lbs. per cow compared to a dry lot.
Match fields to species - Not all forages stockpile equally
Species composition should be considered as an agronomic driver of field selection. While technically any forage can be stockpiled, forages differ substantially in how well they hold quality through the winter and how productively they grow in fall.
Tall fescue is the top-performing species in the Upper Midwest due to its strong late-season growth, upright structure, and durability under snow and ice. It maintains quality well, with only minor declines in crude protein and digestibility from fall through early winter, making it ideal for grazing later in the season after other feeds are used. Soft-leaf, novel-endophyte varieties are recommended to reduce toxicosis risk. Reed canarygrass and orchardgrass are also suitable alternatives, producing comparable biomass when tall fescue is not available, while timothy is less productive and declines in quality more rapidly.
In contrast, smooth bromegrass is poorly suited for stockpiling due to limited fall growth and significantly lower yields, and should generally remain in fall grazing rotations unless no other options exist, in which case it should be grazed early after a killing frost.
Legumes are not well suited for stockpiling and fields dominated by legumes should generally not be designated as primary stockpile paddocks. However, legume content of 30% or more in a mixed stand can supply sufficient nitrogen for fall growth, reducing or eliminating the need for supplemental fertilizer, a consideration worth factoring into both field selection and fertility planning.
Evaluate practical field logistics
Beyond agronomy, winter grazing introduces logistical constraints that should factor into field selection.
Water access is non-negotiable. Stockpiled fields must have a reliable water source that remains functional in freezing conditions. Fields dependent on surface water sources that freeze solid, or that lack tank heaters or frost-free hydrants, are poor candidates unless you can address water infrastructure before the season begins.
Fencing is a second consideration. Stockpile grazing typically involves strip grazing with temporary electric fence to limit waste and extend the duration of the feed supply. However, frozen ground can make step-in posts and reel systems difficult to manage. Evaluate whether your targeted fields have a practical fence layout for winter use and whether the topography and access allow you to move fence efficiently when the ground is frozen or snow-covered.
Agronomic management of selected fields
Once fields are selected, timing and fertility are critical. In the Upper Midwest, fields should be mowed and fertilized in mid-summer - generally late July to mid-August, though the specific window may shift somewhat by region. A nitrogen application of 60-80 lbs. N/acre is standard to promote even, abundant fall growth. As noted above, legume content can reduce or eliminate this nitrogen requirement.
When grazing stockpile in winter, maintain a residual height of at least 4 inches to protect crown and tiller survival through the winter and ensure stand persistence into the following spring.
Stockpiling as part of a broader strategy
It is worth emphasizing that stockpiling works best as one component of a broader winter grazing plan rather than a singular solution. Fall weather creates inherent variability - dry autumns limit fall growth, while wet winters accelerate forage weathering and quality loss. Building redundancy into your system through a combination of crop residue grazing, stockpiled pastures, and stored feed reserves provides the flexibility needed to manage through variable seasons.
The fields you choose to stockpile and the forages growing on them will shape how effective this strategy is for your operation. Matching species to season, aligning field selection with your rotation, and addressing practical access and water needs will position you to get the most out of every acre set aside for winter grazing.
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