How Fruit Size Effects Amount Needed To Fill the Bin

Perhaps the most common thought in the minds of picking crews after they have gone through a well-managed block of apples could be "larger apples fill bins much quicker than average size fruit."

This idea is easily substantiated. Table 1 gives you some idea of relative fruit size and numbers needed to fill the bin. It takes 2000 apples of 3 1/8 inch diameter (100 count size) to fill a bin.

To fill the same bin with 2 ¾-inch diameter (138-count size) fruit, you have to reach for and handle 2760 apples per bin. Although a 2 ¾-inch apple isn't a bad size, time and costs increase when smaller fruit is handled.

Table 1. Number of Apples to Fill Bins (Based on 20 bu/bin and 42 lb/bu)
Size Diameter Number Fruit Size Factor vs. 100's
88 3¼" 1760 1.1
100 3 1/8" 2000 1
113 3" 2260 .9
125 2 7/8" 2500 .8
138 2 ¾" 2760 .7
150 2 5/8" 3000 .6
163 2 ½" 3260 .5
175 2 3/8"   .4
Worksheet Example:

1000 trees/acre x 30 apples/tree = 30, 000 apples/acre = 30, 000 apples
There are 2000 apples per bin of 100 count size.

number of apples ÷ number per bin = 30,000 ÷ 2,000 = 15 bins

Bins/acre = apples/tree x tree density factor x fruit size factor

Tree Density Factor Chart
Trees per acres Tree Density Factor
250 0.13
300 0.16
400 0.2
500 0.25
600 0.3
750 0.38
1000 0.5

 

 

Fruit Size Factor Chart
Count Size per tree Fruit Size Factor
138 0.7
125 0.8
113 0.9
100 1
88 1.1

 

 

Example: Grower has a density of 600 trees/acre and has 40 apples of avg. 125-count size/tree.

The grower needs:
Bins needed = 40(apples/tree) x 0.3(tree density factor) x 0.8(fruit size factor) = 9.6 or 10 bins

Three Factors That Make Up Crop Volume

Three factors make up crop volume: tree numbers, fruit numbers, and fruit size. If fruit size and crop load is fairly uniform in a higher-density planting, you can easily estimate yield. For example, if you have a tree density of 1000 trees/acre, and each tree carries 30 apples of 100-count size; you would need about 15 bins to accommodate the yield from one acre.

At 1000 trees/acre, the bin requirement is equal to half the number of apples per tree if the fruit is 100 count size.

At 500 trees/acre, the number of bins you would need equals one quarter the number of apples per tree. For sizes less than 100 count size (1x), you would multiply by a fruit factor which accounts for a 10% volume reduction for every 1/8-inch loss of size.

The Importance of Thinning for a Standard Distribution

Fruit size in a well-thinned crop generally follows a standard distribution. Most of the crop will be of the desired size classes while a smaller percentage of fruit will be much larger or much smaller than the bulk of the fruit making up the crop.