Spring Dead Spot vs. Dormancy: How to Tell the Difference When Bermuda Wakes Up

Every spring in North Texas, Bermuda grass lawns wake up from dormancy — and for many homeowners, that green-up period brings a new source of anxiety. Most of the lawn flushes green right on schedule, but some spots refuse to come back. Is it just slow dormancy? Root damage from the winter? Or something worse? In a significant number of cases, those stubborn dead patches are spring dead spot disease — and knowing the difference between true dormancy and fungal damage determines whether you do nothing and wait, or call in lawn disease and fungus control before the season gets away from you.

What Is Spring Dead Spot?

Spring dead spot (SDS) is caused by a complex of root-rotting fungi in the genus Ophiosphaerella — primarily O. herpotricha, O. korrae, and O. narmari. Unlike most lawn fungal diseases that attack during active growth, spring dead spot infects Bermuda roots and crowns in the fall when soil temperatures drop below 70°F. The infection progresses through winter while the grass is dormant, so the turf owner has no idea anything is wrong. The damage only becomes visible in spring when the surrounding lawn green-ups and the diseased areas simply don’t.

North Texas — with its alkaline, clay-heavy soils and sharp fall temperature drops — creates nearly ideal conditions for SDS. It’s one of the most destructive Bermuda grass diseases in our region and one of the most frequently misdiagnosed.

What Spring Dead Spot Looks Like Versus Dormancy

The timing and pattern of the dead areas are your two best diagnostic tools when Bermuda starts greening up in March and April:

• Dormancy resolves evenly and progressively: When Bermuda comes out of normal winter dormancy, the green-up spreads gradually and somewhat uniformly across the lawn as soil temperatures rise. Even slow spots tend to follow the same general pattern as the rest of the lawn and show some green within a few weeks of the surrounding turf.
• Spring dead spot stays brown in distinct circles: SDS patches are typically round or oval with fairly defined edges. They range from a foot to several feet in diameter and may appear as a single large circle or as a cluster of smaller rings. The center is completely dead — no green whatsoever — while the surrounding Bermuda greens up normally right up to the edge.
• The patch may have a sunken or collapsed appearance: Because SDS kills the crown and root system, the plant structure collapses. Diseased areas often appear slightly lower than the surrounding turf when viewed at an angle, and pulling on the dead runners reveals roots that are dark, rotted, and easily detached from the soil.
• Weeds colonize SDS patches quickly: The bare soil left by SDS is immediately populated by opportunistic weeds — particularly henbit, clover, and crabgrass — while the surrounding Bermuda greens up. A patch of green weeds surrounded by Bermuda is often the first clear sign to many homeowners that something went wrong over winter.

How to Confirm You’re Looking at SDS, Not Just Slow Dormancy

Two quick checks can help you differentiate SDS from stubborn dormancy before you call anyone:

• The tug test: Grab a handful of the dead runners in the affected area and pull. Healthy dormant Bermuda, even when still brown, will have intact root systems that resist pulling and feel firmly anchored. SDS-damaged roots are black, shrunken, and snap away from the soil with almost no resistance — the crown has rotted away.
• The timing and edge test: If by mid-April your lawn is 80% green and one or more circular spots remain completely brown with sharp edges, that’s SDS until proven otherwise. True dormancy doesn’t leave perfectly circular dead patches with clear boundaries — it produces uneven green-up, not discrete geometric dead zones.

Why North Texas Lawns Are Particularly Vulnerable

Several factors in the DFW region combine to make Bermuda lawns here more susceptible to spring dead spot than in other parts of the South:

• Alkaline soil pH: North Texas soils are frequently pH 7.5 to 8.2. Research consistently shows that SDS severity increases in alkaline soils because the high pH affects Bermuda’s root health and reduces the effectiveness of natural soil microbial suppression of the pathogens.
• Heavy clay soils with poor drainage: Waterlogged conditions in winter accelerate crown and root rot by the Ophiosphaerella fungi. Poorly drained areas and compacted clay zones in DFW lawns almost always show worse SDS damage than well-drained areas.
• Late fall nitrogen fertilization: Applying high-nitrogen fertilizer to Bermuda in late September or October pushes lush growth right before dormancy — the succulent tissue is far more vulnerable to fungal infection than hardened, fall-ready turf.
• High thatch accumulation: Bermuda that hasn’t been verticut or core aerated accumulates thatch that creates a moist, insulated environment at the crown — exactly where SDS pathogens live and spread.

What Happens to SDS Patches If Left Untreated

This is where many homeowners make a costly mistake: they assume the patches will fill in on their own once summer heat arrives. In mild SDS cases with small patches, Bermuda can slowly creep back in by mid-summer. But in moderate to severe infections, the patches don’t fill in — they expand. SDS patches that aren’t treated often grow 25 to 50 percent larger the following spring, and after three or four untreated seasons, some lawns develop overlapping rings that leave bare soil across large portions of the yard.

Treating and Preventing Spring Dead Spot

Effective SDS management is a fall-timed program, not a spring one. By the time the patches are visible in spring, the active infection phase is over — the damage is already done. The goal in spring is recovery; the goal in fall is prevention:

• Fall fungicide applications: Products containing azoxystrobin, propiconazole, or thiophanate-methyl applied in September to early October — when soil temps are dropping through the 70°F range — are the primary prevention tool. Timing is everything; applications made in November are largely ineffective because infection has already occurred.
• Core aeration in fall: Reducing compaction and improving drainage directly in the infection zone reduces SDS severity over time. Annual fall aeration is one of the most valuable cultural practices for SDS-prone DFW lawns.
• Soil acidification in high-pH lawns: Sulfur applications to reduce soil pH over time improve Bermuda root health and reduce SDS pressure. This is a slow process but pays dividends in lawns with consistently high-pH soils.
• Spring patch repair: Damaged patches can be plugged or sodded once Bermuda is actively growing in late May and June. Without fungicide treatment in the following fall, new plugs in the same area are at risk of re-infection.

If your Bermuda lawn woke up this spring with circular dead patches that everyone around them greened up fine, don’t assume it’s just slow recovery. Get it looked at now, start planning your fall prevention program, and stop the cycle before next spring brings bigger patches. Our full lawn disease and fungus control program addresses SDS from both the fall prevention and spring recovery angles. Also see our post on gray leaf spot in Bermuda grass for another commonly confused Bermuda disease.