USDA Zone 4b & Sandy Soil

Hello,
I live in USDA Zone 4b (Minnesota, USA), and I'm having a hard time finding information specific to my area. I can find a bunch of stuff from Montana and that is pretty close to my zone, but specifically to Minnesota, we have really really sandy soil. Basically, I'm looking to grow a food forest but I'm worried about the sandy soil.

Does anyone out there know about any information on working in sandy soil and/or zone 4?

Welcome to the permies forum.

If you have sandy soil the plants will adjust by having a deeper root system as long as you dont encourage a shallow root system by frequent watering.
Another trick is to use swales to capture any water esp seeing as how it drains so much.
Burying wood in the ground will store water more readily and longer (hugelculture).
Planting in depression vs mounds/hill.
Bio-char will allow the trees to get nutrients easier thus needing less water.
A nice fungi network will trade the plants minerals+water for sugars so the plant root doesn't have to work as hard
Fungi have a much better "root" system so they can extra minerals and water way more effective than plants.
Use cultivars/species that are ok with "dry/desert" environments.
Plant your perennials in fall so that they have time to establish the best possible root system.
Even though the trees dont have leaves as long as the soil temp is above freezing, the roots will continue growing and establish themselves for the "dry" spring/summer.

Aaron,
Think of soil building as the major focus of your startup. Use nitrogen fixing cover crops next to your woody species, mulch with wood chips, include permanent nitrogen fixing shrubs/trees in with your desired woody species. Develop a system that produces your mulch needs, include some dynamic acculmulator plants to use in chop&drop mulching (comfrey comes to mind as one prime example). Plant a diversity of species to create the greatest variety of rooting zones (tap rooted, deep rooted branching roots, more shallow net-like rooting plants). The more root mass throughout your soil profile means more dying roots to rot underground to help build humus.
Minnesota receives considerably more moisture than we do here on the east side of the Rockies so this should help your mulches break down faster than they do here. All of the mulching will help you develop your fungal networks so critical to tree success (this fits with S.Bengi's burying wood and using biochar). Good luck and keep building soil. It'll happen!