They say that there is more than one way to skin a cat. This is particularly true with harvesting nuts. The ancient tried and true method is to wait for the nuts to drop to the ground and simply get down and pick them up. This is fine for the supple back, and growers with lots of cheap labour or small plantings. These growers are doing it for fun, not for profit, and there is nothing wrong with that.
Hand tools have been invented by the dozen to reduce the amount of stoop work in the harvest. From soup cans nailed to sticks, to spring tine gadgets and special rakes that pick up nuts one at a time or in scoop fulls, these labour saving devices make the job more enjoyable. A backpack blower/vacuum can speed hand work up and do the work of three or more hand gatherers. One grower uses a grass blower and catching frame to gather his crop.
An invention called a "Bag-A-Nut" picks up nuts between plastic tines on reels with fingers that rakes them off into a bin. Different models are made to handle different sized nuts. The narrowest tined unit picks up hazelnuts, while the widest unit will clean up a house yard of black walnuts in short order. For this to work well, the land needs to have twigs and leaf stalks removed from the orchard floor, otherwise they clog the fingers and sows the harvest.
The latest invention is the "Wizard", an utterly remarkable tool that is produced in several sizes for different size nuts. It is a wire cage shaped like a football with wire bars that spread and capture the nuts inside the ball as it is rolled along the grass. This tool is especially important in the black walnut industry where nuts can be picked up from under trees in almost any location.
For the larger grower with acres to harvest and a profit margin to consider, the above tools are useful for pick your own business and/or light drops and a final once over gleaning. The nut farmer would more efficiently harvest his crops with a three point hitch tree shaker and a mechanized harvester, similar to the units used in the pecan industry farther south, or the blower/sweeper/harvester systems used in the walnut and hazelnut industry of the west coast.
The Lockwood and the Savage 8042 are entry level harvesters because of the limited storage on the harvester. Other models with bin dumpers and trailers following are for larger operations.
All of the harvesters will require a cleaner to separate the remaining debris from the nuts as shown in the breakdown model here. Similar cleaners work on all of the nuts that have dry husks like pecan, Persian walnut, chestnut and hickory.
Once cleaned, the nuts need to be washed, sanitized and dried. If an aggregator handles this part, then the grower stops at the cleaning of the nuts.