HEART ROT OF VIRGINIA PIE IN MARYLAND 

Loggers and sawmill men have been wary of purchasing 

Virginiapinesawtimber. Theypointoutthataheartrot, 

locally called "red heart, may spell the difference between 

profit and loss on a logging job. It is difficult to detect 

this rot in standing Virginia pine. It is even harder to 

estimate the volume loss, And total losses can be determined 

only after logging and milling. 

On the Beltsville Experimental Forest, harvest cuttings were conducted in Virginia pine stands ranging from 

40 to about 75 years old. From observations made during the 

logging job, it appeared that heart rot might indeed be serious, particularly in the older stands. It was noted that 

the occasional tree bearing a fruiting body of the causal 

fungus Fomes pini was often unmerchantable. But other trees 

without this indicator were also found to contain rot, sometimes extensively. 

In view of these observations, which seemed to support the opinions of local loggers, a study was made of 

trees, logs, and lumber from Experimental Forest cuttings. 

The objectives of this study were to determine: (1) the relationship between indications of rot and the volume of unmerchantable wood; (2) the entry points of the rot; and (3) 

the actual merchantable volame loss in a given sawlog sample. 

The results of this study are discussed as answers to 

questions most commonly asked. The findings are based on an 

examination of 168 Virginia pine trees and the sawing of 382 

logs cut from these trees. 

1. How Can One Tell Whether Virginia 

Pine Trees Contain Heart Rot Infection? 

One exterior indication that trees contain heart rot 

is the presence of old or new sporophores--"elephant earsr1-- 

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FOREST RESEARCH NOTES 

NORTHEASTERN FOREST EXPERIMENT STATION 

Upper Darby , Pennsylvania 

No. 56 

1956 

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anywhere along the trunk. These are usually easy to see and 

are strong indications of advanced decay. In this study, 

every tree bearing one or more sporophores yielded cull 

lumber. 

Sawlog-size stands, with most trees ranging between 

12 and 18 inches d.b.h,, will generally have some trees with 

heart rot. 

The age of a stand may be a better indication of rot 

e 

than size of tree. Of the 168 trees sampled, 9 percent contained advanced decay; their average age was 76 years. 

Twenty-two percent contained incipient decay; their age 

averaged 73 years. The remaining 69 percent with no decay 

averaged 67 years old. A 50-year-old stand cut for pulpwood 

showed no heart rot. 

There did not seem to be any definite correlation of 

heart rot with other abnormalities such as old and new pitch 

a 

flows from branch stubs, excegsive limbiness, fire scars, 

wounds, general low vigor of the tree, and Cronartium cerebrum galls, 

2. How Much Loss From Heart Rot Can Be 

Expected In A Mature Virginia Pine Stand? 

In the study, about 2 percent of the 18,752 board 

feet of lumber produced was rejected because of rot. This 

is probably the minimum loss that would be experienced from 

similar stands. 

Nearly 15 percent of the lumber volume, however, 

showed varying amounts of incipient decay, characterized by 

red staining of the heartwood, Lumber thus affected is 

suitable for most purposes; so this is not an important fac- a 

tor in pine utilization. 

But more serious is the fact that, in the tree, the 

incipient stage can develop into advanced decay rather 

rapidly. Only a few years1 additional growth of a mature 

Virginia pine stand may therefore result in a marked increase in loss from heart rot. 

3. hbt Can Be Done To Lessen 

The Amount Of Heart Rot Infection? 

It is believed that most infections become established through old branch stubs that provide direct access 

totheheartwood. Virginiapine is verylimby; the dead 

branches often persist through maturity without being overgrown. As a preventive measure to minimize this means of 

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heartrot entry, progressive pruning of at least the first 

log length of selected crop trees is suggested. It is unlikely that trees become infected through superficial injuries or wounds that do not expose heartwood. 

4. What Portion Of The Tree 

Is Most Subject To Infection? 

As a rule, infection is found in the lower part of a 

tree. This portion is most likely to have rotten branch 

stubs, which may provide an avenue of infection at any time. 

Nearly 90 percent of the cull lumber produced in this study 

was from the butt logs. No rot was found in any portion 

above the second log. 

5. When Heart Rot Is Found In A Log, 

What Deduction Should Scalers Apply? 

The following scaling practices (based on the limited 

observations made during this study) may be used as a rough 

guide for Virginia pine sawlogs. Results of further studies 

may modify these. 

A. Total cull 

1. Logs with two or more sporophores several feet apart. 

2* Logs with one or more sporophores and visible rot at 

both ends. 

3. Logs without sporophores but with visible rot at 

both ends. 

B. Fifty percent cull 

1. Logs with one sporophore and no visible rot or at 

one end only. 

2. Logs without sporophores but with incipient rot at 

both ends. 

C. No cull 

1. Logs without sporophores but with incipient rot at 

one end only. 

2. Logs with any of the abnormalities listed in the answer to question No. 1. 

One important point to consider, even before felling 

and bucking, is that rot may be so extensive that a tree 

will not pay its way out of the woods. Trees in this condition would be those with fruiting bodies so spaced that 

they could not be contained on one log. 
6. Is Heart Rot Likely 

To Affect Yield Of Pulpwood? 

Losses from heart rot in pulpwood stands are apparently so small they can be discounted. An examination of 

several hundred random pulpwood bolts from a 40-year-old 

Virginia pine stand disclosed only one instance of heart 

rot, and it was but a trace. Most pulpwood is produced from 

stands no older than this or is taken from the unaffected 

tops of sawlog trees. 

--RICHARD H. FENTON 

Northeastern Forest Experiment Station 

Forest Service, U.S . Dept. Agriculture 

and 

FREDERICK H. BERRY 

Horticultural Branch 

Agricultural Research Service 

U .S . Dept . Agriculture 

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