American Hazelnuts: My Only Reliable Crop?

A walk-through showing some of my American Hazelnut (Corylus americana) bushes in late August, a couple weeks before prime harvest time begins. My garden is in USDA zone 5b, in Lawton, MI (42° North latitude), and is on very poor, dry, sandy soil, in addition to being in a frost pocket that gets all of the late spring frosts. We average about 33" of rain per year here. Hazelnuts (mine are all seedlings, no cloned cultivars) have proven to be a very hardy crop on my poor site, producing after a few seasons in the ground, tolerating pressure from deer and rabbit grazing, mole and groundhog tunneling, polar vortex winters, yearly droughts, neglect, and more. Note that my site was a big grassy field when I got it, so squirrel pressure is low or nonexistent in most of my garden, though that will change as it matures and the tree canopy develops. So far I have about 150 bushes planted around my 3+ acres, some in mixed hedgerows, some as standalones or clusters, and some that wildlife have planted for me from previous years' crops. Mine are a mixture of unselected wild-type seedlings, selected seedlings from New Forest Farm (Mark Shepard's nursery), and a handful from Oikos Tree Crops. Note that hazelnuts were the dominant shrub species in the oak savanna ecosystems in this part of the world before colonization and white settlement, they were adapted to the fire regime and were probably important to the diets of a lot of wildlife and people. My site was an oak savanna 200 years ago, and my grandmother remembers hazelnuts around the property in the 1940s, those may be some of the same ones that are still around on the margins.