Timothy

Timothy (Phleum pratense L.) is a cool-season perennial bunchgrass most widely grown for hay; as a cover crop it’s valued for quick spring ground cover, soil protection, and the option to harvest quality forage. Growers choose timothy when they want a winter-hardy grass that fits well with legumes, provides surface cover to limit erosion, and scavenges leftover soil nitrogen. [NRCS Plant Guide—Timothy] ((plants.usda.gov)) [UMaine Forage Facts—Timothy] ((extension.umaine.edu))

Benefits of Timothy as a Cover Crop

• Erosion Control: Dense grass cover and residue can sharply reduce sediment loss. Recent USDA NRCS on-farm work found cover crops reduced erosion by 60–70% in no‑till systems; broader SARE syntheses report non‑legume covers (grasses) reduce soil loss 31–100%, with large ton-per-acre reductions where fields would otherwise be bare. [NRCS CIG progress report, 2024] ((cig.nrcs.usda.gov)) [SARE—Covering the Soil to Prevent Erosion] ((sare.org))
• Weed Suppression: Like other grasses, well‑established timothy competes for light and nutrients and creates a residue mulch after termination. A 2024 meta‑analysis across field studies found cover crops reduced weed biomass on average by about 83%, with strongest effects from grasses; suppression improves as cover‑crop biomass increases. [Weed Science meta‑analysis, 2024] ((cambridge.org))
• Soil Structure Improvement: Grasses provide a fibrous root mat that binds surface soil; NRCS summaries show cover crops increased infiltration by ~58% in a 3‑year Coastal Plain study and improved saturated hydraulic conductivity up to 3.6× when a grass/legume cover was added, indicating stronger aggregation and pore networks. [NRCS soil health literature—Infiltration/Ksat/Runoff] ((nrcs.usda.gov)) [NRCS Plant Guide—Timothy root system] ((plants.usda.gov))
• Water Management: By protecting the surface and opening macropores, grass covers reduce runoff and improve infiltration; recent ARS work in conservation systems also shows each additional Mg/ha of cover‑crop biomass can measurably improve pre‑plant soil water status and rainfall infiltration. [USDA‑ARS 2025/26 research summary and article] ((ars.usda.gov))
• Disease/Pest Break: As a non‑legume grass, timothy is a non‑host for key legume pests such as soybean cyst nematode; rotating to non‑host crops (grasses/small grains) between soybean years helps drive SCN populations down, especially when used for multiple seasons at high infestation levels. [UMN Extension—SCN management] ((extension.umn.edu))
• Nitrogen Management (scavenging): Grasses are very effective N catch crops; NRCS notes a good cover crop (especially mixes with grasses) can scavenge 40+ lb N/acre, and where high biomass is achieved, grass covers commonly tie up 100+ lb N/acre in tissue—N that would otherwise be leachable. Plan N for the next crop accordingly if residue is mature/high C:N. [NRCS—Prevented Planting Cover Crops (2024 update)] ((nrcs.usda.gov)) [SARE—Building Soils for Better Crops (grasses scavenge N) and Managing CCs in conservation tillage (N dynamics)] ((sare.org))
• Biomass Production: Under moderate management, annual hay yield for timothy averages near 2 tons/acre in the Northeast (often with ~70% of yield in the first cutting), providing ample surface residue if used as a cover/forage. [UMaine Forage Facts—Timothy] ((extension.umaine.edu)) [UK Extension—Timothy (AGR‑84)] ((publications.ca.uky.edu))

Planting and Management Advice

• Seeding Rate (drill and broadcast):
• Pure stand (drilled): 4–6 lb/acre PLS (Kentucky guidance) or 5–10 lb/acre PLS (Maine). Use the higher end when rapid ground cover is the priority. [UK Extension—AGR‑84] ((publications.ca.uky.edu)) [UMaine Forage Facts—Timothy] ((extension.umaine.edu))
• In mixtures with legumes (drilled): 2–4 lb/acre timothy. [UK Extension—AGR‑84] ((publications.ca.uky.edu))
• Broadcast: If broadcasting rather than drilling, NRCS recommends doubling the drilled seeding rate to compensate for poorer seed‑to‑soil contact; for a pure stand that’s typically 8–12 (up to 10–20) lb/acre depending on your drilled target. Firm (cultipack) after broadcasting. [NRCS MT Plant Materials Tech Note MT‑46—doubling for broadcast] ((nrcs.usda.gov))
• Seed count (for calibration): ~1.23 million seeds/lb. [NRCS Plant Guide—Timothy] ((plants.usda.gov))
• Seeding Depth: Very shallow—1/8 to 1/2 inch in a firm, fine seedbed; shallow placement is critical for uniform emergence. [NRCS Plant Guide—Timothy] ((plants.usda.gov)) [UMaine Forage Facts—Timothy] ((extension.umaine.edu))
• Soil Type and pH: Best on fine‑textured loams to clays with good fertility; adapted to moist, cool sites. Soil pH range ~5.5–7.0 (target near 6–7 for best performance; Pennsylvania guidance often targets pH 6.5). [NRCS Plant Guide—Timothy] ((plants.usda.gov)) [Penn State “Planting Timothy” sheet] ((agsci.psu.edu))
• Planting Time (seasonal windows by region):
• Northeast (e.g., ME): Spring (late April–early June) or late summer (late August–September); sow 6–8 weeks before first frost for fall seedings. [UMaine Forage Facts—Timothy] ((extension.umaine.edu))
• Mid‑Atlantic (PA): Timely fall window for timothy seed crop establishment centers on about Aug 5 – Sept 20. [Penn State Cover Crop Species Selection—Timothy row] ((extension.psu.edu))
• Midwest (IA): For late‑summer establishment, complete seedings by about Aug 10 (north), Aug 20 (central), Sept 1 (south); Kentucky bluegrass/orchardgrass/timothy may be seeded two weeks later than these dates if moisture is adequate. [Iowa State ICM—Late Summer Establishment] ((crops.extension.iastate.edu))
• Western mountains/irrigated: Plant before or early in the two‑month period most favorable to germination; June–early July at high elevations; August under irrigation. [USFS FEIS—Timothy] ((research.fs.usda.gov))
• Termination (methods and timing):
• For use strictly as a cover, plan termination at least 2 weeks before the cash crop (or at‑plant/shortly after in some systems) via herbicide, tillage, mowing/grazing plus tillage, or a combination. Being a winter‑hardy perennial, timothy will not winter‑kill reliably—budget for chemical or mechanical termination. [Penn State Cover Crops—Species Selection/termination timing] ((extension.psu.edu)) [NRCS Cover Crop Standard (Code 340)] ((nrcs.usda.gov))
• Rotational Considerations:
• Excellent ahead of broadleaf crops (soybean, canola) from a pest‑rotation perspective because grasses are non‑hosts for SCN; multiple non‑host years may be needed to markedly lower very high SCN populations. [UMN Extension—SCN management] ((extension.umn.edu))
• If timothy is allowed to mature to heading, expect higher C:N residue that can temporarily immobilize N; SARE guidance indicates late‑terminated grass residues can require 20–30 lb additional N/acre to offset tie‑up. [SARE—Managing Cover Crops in Conservation Tillage Systems] ((sare.org))
• Water Requirements and Drought Tolerance:
• Timothy thrives in cool, moist environments and is notably less heat/drought hardy than many hay grasses; it is best adapted where effective annual precipitation is ≥18 inches. [NRCS Plant Guide—Timothy] ((plants.usda.gov)) [UMaine Forage Facts—Timothy (less heat/drought hardy)] ((extension.umaine.edu))

Practical notes to maximize success:

• For faster canopy and better weed suppression, seed on the early side of the regional window, ensure a firm seedbed, and consider including a small amount of a quick‑establishing species or a legume (with reduced timothy rate) if forage harvest is planned. [UK Extension—AGR‑84] ((publications.ca.uky.edu))
• Aim for strong biomass if weed suppression is a priority; across studies, grass cover crops deliver the most reliable reductions, and suppression scales with biomass. [Weed Science meta‑analysis, 2024] ((cambridge.org))
• Expect meaningful infiltration/runoff improvements as cover persists; documented gains include ~58% higher infiltration and multi‑fold increases in Ksat with grass‑inclusive covers. [NRCS soil health literature—Infiltration/Ksat] ((nrcs.usda.gov))

Easily overlooked constraints:

• Establishment is relatively slow compared with oats/rye; fall seedings often face less weed pressure and succeed more consistently than spring in the Northeast and Upper Midwest. [UMaine Forage Facts—Timothy] ((extension.umaine.edu))
• Because it’s winter‑hardy, plan termination—don’t assume winter‑kill. Terminate at least 14 days before planting a spring cash crop to minimize interference. [Penn State Cover Crops—termination timing] ((extension.psu.edu))