Heterobasidion Root Disease Interactive Guide
Result
HRD is present in the stand.
Learn more in Chapter 4 of the HRD guidelines.
Recommendation
If harvesting occurs from April 1–November 30, preventive stump treatment on pine and spruce is recommended if more than 50% of the stand is pine and/or spruce. The minimum tree size for treatment is merchantable size. No treatment is required from December 1–March 31. Harvesting without preventive stump treatment can be considered April 1–November 30 on certain conditions listed as Exceptsions or Modifications in the HRD stump treatment guidelines.
Exceptions/Modifications
During unusual weather patterns, Chapter 4, Modification 1 may apply. Examples of unusual weather conditions include but are not limited to:
- Prolonged, unusually warm weather during the winter period (December 1–March 31), treatment may be recommended.
- Prolonged, unusually cold weather outside the winter period (outside of December 1–March 31), treatment may not be necessary.
- Deep snow cover (at least 12 inches) outside of the winter period (outside of December 1–March 31), treatment may not be necessary.
Things to consider
It is possible that H. irregulare is present in a stand where the disease has not been confirmed. If you choose to harvest during April 1–November 30 without stump treatment, consider the potential impact to the stand and subsequently to adjacent stands if HRD were to develop in the stand. It is important to not that there are no treatments to eradicate the pathogen after it infests a stand.