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Pecan Tree Nut Problems: Weevils, Scab, and Spray Schedule

Pecan tree (8″ DBH, 2 years post-vine removal) had hollow nuts last year. This year: abundant nuts but dropping, light purple powder on husks, water inside kernels. Variety unknown ("pig pecan"?).

Three Issues

Water in kernel = normal early development
Circular holes = pecan weevil (1/10″ holes)
Purple/gray fuzz = pecan scab (fungal)

Spray Program (Next Spring)

Bud break: Sevin (insecticide) + Daconil (fungicide) mixed
2 sprays, 14 days apart early season
Then every 3 weeks through August
Critical during rain

Resources

MSU Cares "homeowner pecan" publications for detailed schedules.

Shorter tree = easier spraying. Good luck.

Plant Diseases: Ash Tree Marginal Scorch: Root Stress, Not Disease; Diagnosing Lilac Decline: Root Rot and Herbicide Injury; Saving a Dying Palm Tree: Identifying and Treating Trunk Rot; Pecan Tree Limb Drop: Drought, Weevils, and Borers; Plum Tree Leaf Curl and Eggs: Beneficial vs. Pest Identification; Tulip Tree Troubles: Sapsucker Damage and Basal Decay; Pecan Nuts Moldy or Shriveled: Water Stress, Not Disease; Pecan Tree No Nuts: Water, Zinc, Fertilizer, Pruning Guide; Kwanzan Cherry Oozing Sap: Bacterial Canker or Mechanical Injury?; Pecan Trees Not Bearing: Fertilize, Water, Soil Test

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