No. 11 

NOVEMBER i 951 

SEARCH NOTES 

UPPER DARBY PA R. W .MARQUIS DIRECTOR 

A GUIDE FOR SALVAGING WHITE PINE 

[NURED BY FOREST FIRES 

White pine forests are severely damaged by 

forest fires. Generally a fire kills all trees 

less than 20 feet high immediately. Larger 

trees may die later, depending on the degree of 

injury. Salvage operations must be started soon 

after a fire, because insects and fungi quickly 

e attack trees that are killed. 

So when white pine lands burn, awnerg are 

faded with three questions: (1) Which white pine - u% 

trees should be cut first? (2) Which trees 

should be left to produce seed? (3) Which trees 

will recover fully? 

A Study Of Sumrival 

Immediately after the forest fires that 

swept parts of southern Maine in October 1947, a 

study of fire-damaged trees on the Massabesic 
Experimental Forest WE++ started. One hundred 

twenty-txo sample trees "were selected for study 

in an attempt to' find out . the relationships 

among degree of injury, size of tree, and 

survival. 

The trees selected for study were classed 

as small (2-6 inches in diameter), medium (7-11 

inches), and large (12 inches or more). They 

represented four combinations of injury: 

Root Crown 

injury in*jury 

Light - Light 

Light - Heavy 

Heavy - Light 

Heavy - Heavy 

Root injury was considered light if 25 percent or less of the visible roots were killed or 

severely injured. Injury was heavy if 75 percent or more of the major surface roots were 

killed or severely iqjured. Allowance was made 

for roots only partially damaged. 

Crown injury was considered light if onethird or less of the crown was scorched. Injury 

was heavy if two-thirds or more of the crown was 

scorched. No trees were included that had their 

crowns entirely consumed by fire. 

0 

 h he study was limited to trees that represented the extremes of damage: light or heavy. 

Trees with intermediate degrees of injury were 

not included. 1 

These sample trees have been examined every 

year since the fire. Table 1 shows the results 

t~ date. 
Some Answers Are APPearing 

In general, the larger the tree, the better 

its chance to survive fire. Smaller trees-- 

6 inches and less in diameter at breast height-- 

readily succumb to heavy injury of either roots 

or crown. In trees of all sizes, root injury 

seems to be more serious than crown injury. 

When salvage priorities are set up, coma pletely killed stands should be cut first. Next 

Table 1.-Surrival of white pine following fire 

Degree of injury 

Percent Percent Percent 

Root injury light- . 

Crown injury light 1947 100 100 100 

1948. 100 90 90 

1949 100 90 70 

1950 75 80 70 

Root injury lightCrown injury heavy 1947 100 100 100 

1948 100 77 50 

1949 86 69 20 

1950 86 54 20 

Root injury heavyCrown injury light 1947 100 100 100 

1948 70 50 20 

1949 70 50 0 

1950 60 40 - 

Root in jury heavyCrown injury heavy 1947 100 100 100 

1948 78 36 10 

1949 33 27 10 

1950 22 2 7 10 

Year 

Survival by tree size 

Large 

trees 

Meaum 

trees 

Small 

trees 
are the stands where $he root systems of all or 

most of the trees have been severely damaged; 

and stands of smaller trees should be given the 

highest .-riority. In stands where root injury 

was not neavy--and especially if crown injury 

was light--salvage cutting can be delayed at 

least 1 year. 

. , !dherever possible, 25 or more trees per 

acre should be left as seed trees. White pine 

seed requires two grming seasons to mature and 

seed years generally occur at intervals of 3 to 

5 years; so trees that have heavy root damage 

are poor risks for seed trees. The best seed 

trees to leave are those more than 12 inches 

d. b. h. that have only light root injury. Medium 

and srnall trees can also be left if root and 

crowrl injury is light, 

--THOMAS W. McCOBKEY and DONALD R. GEDNEY 

SOME RECENT PUBLICATIONS 

i 

Ferguson, RolandH. Who Likes spare roots? Jour. 

Forestry 49: 653. 1951. 

Rettie, James C. Forests and YOU. Pa. Forests 36: 

82. 1951. 

Storey, Herbert C. A milestone in conseruation.. . a 

nat20naL mter resources fid2cy. Pa. Forests 36: 76-77, 

80. 1951. 

4 AGRICULTURE - FOREST SERVICE - UPPER DARBY. PA.