Teff Grass

Teff (Eragrostis tef) is a warm-season annual C4 grass grown in the U.S. primarily as a fast-establishing summer cover or high-quality hay. Growers choose teff because it germinates quickly on a firm seedbed, creates a dense, weed‑suppressing canopy in 3–4 weeks, and produces useful biomass with relatively modest fertility and water compared to many forages. (ohioline.osu.edu, climatehubs.usda.gov)

• Erosion Control: Well-managed cover crops can reduce soil loss by 31–100% (non-legumes like grasses) and cut sediment losses by an average 20.8 tons/acre under conventional till and 1.2 tons/acre under no‑till; teff functions as a summer grass cover delivering these erosion-control benefits when actively growing. (sare.org)
• Weed Suppression: Teff forms an “extremely dense canopy” and reached effective cover in as little as 3 weeks in University of Rhode Island field work; using teff alleys in pumpkins cut pre‑emergent herbicide use by 50%. In 2021 Australian field trials, teff cover reduced in‑season weed biomass by 90–95%, and its residue suppressed subsequent weed emergence by up to 73%. (climatehubs.usda.gov, mdpi.com)
• Soil Structure Improvement: As a fibrous-rooted grass, teff contributes roots and residues that promote macropores and aggregation; across systems, cover crops increase infiltration and improve tilth through living roots and organic matter inputs. Reported teff root depth varies widely (about 59–117 cm) among genotypes, supporting soil aggregation and pore formation near and below the surface. (sare.org, cabiagbio.biomedcentral.com)
• Water Management: Cover crops have increased infiltration by 8–462% (grasses up to 462%) and, in some systems, more than six‑fold, improving water storage and decreasing runoff. Teff’s summer growth window and dense surface cover help reduce crusting and runoff during intense storms. (sare.org)
• Disease/Pest Break: Cover crop residue reduces splash dispersal of soil‑borne pathogens; as a grass, teff also breaks cycles of broadleaf crop diseases. Recent work found teff is a non‑host for potato cyst nematode (Globodera pallida), allowing it to be grown safely in infested fields without increasing PCN populations. (sare.org, journals.flvc.org)
• Nitrogen Management: As a non‑legume, teff scavenges residual soil N. Across studies, non‑legume cover crops reduced N losses to water by a median 48% (up to 89%) and typically take up 30–50 lb N/acre—up to ~150 lb/acre where residual N is high—keeping N in the field for the next crop. (sare.org)
• Biomass Production: Typical forage/cover biomass in the Midwest is about 2–4 tons dry matter (DM)/acre, with >5 tons/acre under good conditions; Utah trials commonly achieve 4–5 tons/acre with good management. In Northeast vegetable systems, URI trials measured ~1, ~2, and nearly ~3 tons DM/acre at 6, 8, and 10 weeks, respectively. (ohioline.osu.edu, extension.usu.edu, climatehubs.usda.gov)

• Seeding Rate (drill and broadcast):
• Drill, raw seed: 4–6 lb/acre (common extension recommendation). Drill, coated seed: 8–10 lb/acre (some guides allow 8–12 lb/acre). (ohioline.osu.edu, extensionpubs.unl.edu)
• Broadcast: 4–7 lb/acre (Virginia Tech table; broadcast then cultipack); many practitioners use 5–10 lb/acre depending on coating and conditions. Always firm the seedbed. (ext.vt.edu)
• Seeding Depth:
• 1/8–1/4 inch into a very firm, smooth seedbed; emergence drops sharply if seed is deeper than 1/4 inch (never deeper than 1/2 inch). (ohioline.osu.edu, extensionpubs.unl.edu)
• Soil Type and pH:
• Best on well‑drained, firm seedbeds; handles marginal or heavy soils better than many warm‑season grasses. Target pH 6.0–6.5. Field experience shows teff can perform on difficult sites (e.g., heavy clays or even high‑pH/saline spots) with good establishment, but optimum growth is near neutral pH. (ext.vt.edu, ohioline.osu.edu, extension.usu.edu)
• Planting Time (seasonal windows by region):
• Mid‑Atlantic/Southeast: Seed from early May once soil ≥60°F. (ext.vt.edu)
• Midwest/Ohio Valley: Late May–mid‑June when soil reaches ~65°F. (ohioline.osu.edu)
• Northeast (coastal New England): Suited to cooler summers; expect rapid canopy within ~3 weeks when seeded after last frost and warm soil; allow ≥10 weeks for maximum biomass before termination. (climatehubs.usda.gov)
• Pacific Northwest: Plant after last killing frost when 4‑inch soil temp >60°F; teff does not tolerate freezing at any stage. (extension.oregonstate.edu)
• Termination (methods and timing):
• Mow (flail) to mulch, till incorporate, or harvest as hay. Teff is not suited to roller‑crimp termination. Regrowth is minimal if mowed in September or later; plants will winter‑kill if left standing. Residue is easier to incorporate than cereal rye or sorghum. (climatehubs.usda.gov)
• Rotational Considerations:
• Teff’s fine crowns/roots leave a friable seedbed that’s easy to work for the next crop; it’s commonly used as a short‑season bridge between alfalfa stands or small grains. Avoid fields with heavy grassy weed histories (limited grass‑weed herbicide options in‑crop). High‑C:N grass residues can temporarily immobilize N; plan starter N for the next crop or allow decomposition time. (forages.oregonstate.edu, extension.usu.edu, southern.sare.org)
• Water Requirements and Drought Tolerance:
• After establishment, teff is relatively drought tolerant for a grass. In irrigated systems, Oregon trials concluded teff needs only about half the irrigation water of alfalfa to achieve optimum yields; Utah growers report 6–12 inches of water per cutting depending on system and climate. (extension.oregonstate.edu, extension.usu.edu)

Additional practical notes:

• Establishment keys are a weed‑free, very firm seedbed and precise, shallow placement. Brillion‑type seeders or broadcasting followed by cultipacking often outperform drills for such tiny seed. (extension.oregonstate.edu, ext.vt.edu)
• Fertility: Split‑apply modest N (about 50–60 lb N/acre at planting and after first cut when growing for forage); excess N can cause lodging. For cover‑only plantings aimed at N scavenging, skip or minimize N fertilizer to encourage uptake of residual soil N. (extension.oregonstate.edu, ext.vt.edu)
• Pest management: Broadleaf weeds can be controlled with labeled postemergence options in some regions; plan pre‑plant weed control as teff is slow for 2–3 weeks after emergence and grass‑weed herbicides are limited. (climatehubs.usda.gov, extension.usu.edu)

This guidance synthesizes university extension, USDA/SARE, and recent research so you can confidently fit teff into summer windows for weed suppression, erosion control, and biomass, then transition smoothly into fall cash crops.