Walnut Soft Shell

Walnut soft shell Common name Walnut soft shell Causal agent There can be multiple reasons behind soft, mushy walnut shells. These include walnut husk fly and vinegar fly infestation, lack of nutrients, environmental stress, and Botryosphaeria or Phomopsis infection. This leads to reduced husk and kernel integrity as well as hull breakdown. Symptoms & Signs The best identification of walnut soft shells is the presence of yellow maggots inside the husk of soft, black walnuts. Conversely, vinegar fly larvae are white in color, which distinguishes them from others. Another common symptom of soft shells is wilting or rot due to irregular irrigation. Transmission If the walnut soft shell is caused by walnut husk or vinegar fly, it can spread to other plants through the larvae. Time of concern Throughout the year Common hosts Walnut