Yellow Rings Around Trees: Nutrient Competition or Shade?

Diagnosing the Problem

Yellowing Bermuda grass around tree trunks typically stems from two causes:

• Nutrient theft: Tree roots outcompete grass for nitrogen, especially at the drip line.
• Insufficient light: Bermuda needs 6+ hours of direct sun; even 5 hours causes thinning.

Why Lime Didn't Work

Lime raises pH but doesn't add nitrogen or fix shade. If soil pH was already adequate, lime has no effect.

Organic Solution

1. Apply compost or well-rotted manure under trees (avoid trunk contact).
2. Broadcast sugar (1 lb/250 sq ft) to boost microbial activity.
3. Add alfalfa meal or lava sand for sustained nutrition.

Commit fully to organics—mixing chemicals cancels benefits.

If Shade Is Primary

• Hire an arborist to thin canopy (not top) for more light.
• Or replace grass with shade-tolerant groundcovers (pachysandra, liriope).