Various formulae for estimation of leaf production in mulberry trees were investigated and obtained. Four varieties of mulberry trees were used as the materials, and seven characters namely branch length. branch diameter, node number per branch, total branch weight, branch weight except leaves, leaf weight and leaf area, were studied. The formulae to estimate the leaf yield of mulberry trees are as follows: 1. Varietal differences were appeared in means, variances, standard devitations and standard errors of seven characters studied as shown in table 1. 2. Y

=a

X

P

......(l) where Y

means yield per l0a by branch number and leaf weight determination. a

.........leaf weight per branch. X

.......branch number per plant. P

........plant number per l0a. 3. Y

=(a

S. E.

X

)+P

.......(2) where Y

means leaf yield per l0a by branch length and leaf weight determination. a

......leaf weight per meter of branch length. S. E. ......standard error. X

....total branch length per plant. P

........plant number per l0a as written above. 4. Y

=(a

S. E

X

)

P

.....(3) where Y

means of yield per l0a by branch diameter measurement. a

.......leaf weight per 1cm of branch diameter. X

......total branch diameter per plant. 5. Y

=(a

S. E.

X

)P

......(4) where Y

means leaf yield per 10a by node number determination. a

.......leaf weight per node X

.....total node number per plant. 6. Y

5/= {(a

5/

S. E.

X

)Kv}

P

.......(5) where Y

5/ means leaf yield per l0a by branch length and leaf area measurement. a

5/......leaf area per 1 meter of branch length. K

v/......leaf weight per 100

of leaf area. 7. Y

6/={(X

a

6/

S. E.)}

K

v/

P

......(6) where Y

6/ means leaf yield estimated by leaf area and branch length measurement. a

6/......branch length per l00

of leaf area. X

, K

v/ and P

are written above. 8. Y

7/= {(a

7/

S. E.

X

)}

K

v/

P

.......(7) where Y

7/ means leaf yield estimates by branch diameter and leaf area measurement. a

7/......leaf area per lcm of branch diameter. X

, K

v/ and P

are written above. 9. Y

8/= {(X

a

8/

S. E.)}

K

v/

P

.......(8) where Y

8/ means leaf yield estimates by leaf area branch diameter. a

8/......branch diameter per l00

of leaf area. X

, K

v/, P

are written above. 10. Y

9/= {(a

9/

S. E.

X

)

K

v/}

P

......(9) where Y

7/ means leaf yield estimates by node number and leaf measurement. a

9/......leaf area per node of branch. X

, K

v/, P

are written above. 11. Y

10/= {(X

a

10/

S. E.)

K

v/}

P

.......(10) where Y

10/ means leaf yield estimates by leaf area and node number determination. a

10/.....node number per l00

of leaf area. X

, K

v/, P

are written above. Among many estimation methods. estimation method by the branch is the better than the methods by the measurement of node number and branch diameter. Estimation method, by branch length and leaf area determination, by formulae (6), could be the best method to determine the leaf yield of mulberry trees without destroying the leaves and without weighting the leaves of mulberry trees.