132. 



Mineral salts are mostly in the leaves. 



From Buesgen we obtain the following figures: In IQOf of dry 



leaves: , 



Conifers: ashes form **^j 



Hardwoods: ashes form 4--7> 



In some species, as ash and black locust, the abhes run as :iigh 



as & ' -9/ , or 8-9# per 100#. 



The young bark is mostly ash. 

 Ash in bark of conifers forms 1-2; 

 M hardwoods 2*4/*. 



The smallest amount of ashes is in the limbs: 



Pine 0.2-0. 2V 



Hardwoods 0.3-0.4 %. 



b.&. The mineral matter taken from the soil per yenr by forest tre 

 is largely spent in building up leaves and small twigs; only a small 

 amount 'ifi used in building up wood. 



In 100J of dry substance: 



1) Hardwoods: . 



Leaves and twigs: 50#, of which 6% or 3# are ashes. 

 Wood (timber) : 50$ 9 of which 0.4# or 0.2# are aafc 



Total ash is 3.2# per lOOa 



Therefore from 32# of salt: 30# goes to leaves and twigs, and 2g 

 to timber; therefore only 1/16 of all mineral matter goes to timber, tt 

 other 1^/16 to the leaves and twigs, the bulk of which is dropped ever^ 

 year. 



2) Conifers: (kept 4 years) 



Leaves and twigs: 2?#,of which 3>< or 0*75* B ash. 

 Wood : 75tf, of which 0.2 or Q.15* **** 



Total ash is 0.8^ per 100* 



There are here only i# of ashes as agaiufct 3^ ashes in hardwoodi 

 therefore conifers can do better on sand than hardwoods. 



N. forms 16^ of dry protopias^i and therefore is absolutely 

 essential. No N and no growth. Gather ^reen leaves: 

 Young leaves contain 4>. N. 

 Old leaves are poorer: 2-0. ^A ** (Heavier in minerals). 



It is an old story that one acre needs a minimum of 40-^'0# of 

 per year. Conifers need less than hardwoods, supposedly 35-40$ per yea 



The amount of K and P 2 5 increases in each leaf from budding to 

 dropping of leaf. They are carried to it by solution and am left by 

 evaporation, as are also other minerals, tho most of them decrease. 



In 1000$ beech leaves: May O.Jl gnu K 



Oct. 0.80 gnu and more,K. 



This increased the amount almost double. The same was true of 

 phosphoric acid. 



In 100# leaf ash : Ca and Mg are richest in fall; 



K and PpOt; are richest in spring. 

 May K: 31^ P20J: 21# 

 July 7 

 fall 3 



