When looking at food sources to plant and manage for the staple game species on your property it's important to know their feeding habits. The vast majority of game species will be either grazers, browsers or opportunistic omnivores.
Grazers are animals like bison or elk that mainly eat a diet of grass and forbs. Some are more strict like bison eating almost all grass whereas elk will tend to eat some woody browse plants as well. When creating a property geared mostly towards a grazing species you'll want to have a higher proportion of grass and forbs as opposed to woody species. This can be done by planting native grass and meadow mixes with species known to be highly palatable to the species you're managing for, as well as species that's adapted to your specific climate. There are many species of grasses and forbs that are unpalatable to wildlife so make sure to do your research to find the right mix of species. I would also always advise you have a high diversity seed mix. Some will naturally do better than others on your specific site so by planting a large variety you'll be ensuring that at least some will do well and self propagate. This type of habitat is usually considered an early successional habitat, which means that it has the potential to transition to more of a brushfield or forest if there are a source of woody plant seeds nearby. In order to manage this properly you may need to mow, clear brush or burn this habitat every so often to keep it in the grass/forb stage. But if managed properly this type of habitat could become a mecca for grazing game species.
The next type of game are browsers. These are species like deer, moose and beaver that mainly feed on the leaves, stems, buds and bark of woody plants. These will generally be broadleaf plants as opposed to conifers and will usually want to be kept short enough so that they can be reached by game. On most sites this will mean planting mainly shrubs and small trees with highly palatable foliage. Again do your research and figure out the best species for the game in your area and figure out which plants will self propagate on your site. Also remember to plant a large variety of species to add diversity to the ecosystem. With this habitat type the main concern will be keeping the new growth within reach of game. This can be done by one, selecting species that are naturally shorter and tend to sprout from the roots and two by every so often cutting back branches or trunks that have grown too high also known as coppicing. Burning might also be a good strategy after so many years but this will depend a lot on the specific plant species you are growing as well as your overall management strategy for the property. This type of habitat will likely be the main focus for most properties due to deer being the best species to manage for in most areas in America.
The last type of game we'll be looking at are generalist omnivores. These game species usually will have a very variable diet, but will tend to focus on calorie dense foods such as nuts, fruits and tubers. Some examples of game animals that fit this category are bears, pigs and turkeys. With these species you'll definitely want to do your research and figure out their preferred foods, but we still can look at some general rules that will apply to most omnivores. The most calorie dense wild plant foods available will generally be nuts also referred to as hard mast. Species such as walnuts, pecans, chestnuts hazelnuts and oaks are all great examples. These tend to be trees or shrubs and depending on the species could be a very productive food source for many wildlife species. The main downside for nut bearing plants is that it is a highly seasonal food source generally lasting only for a few months in the fall. This could be good because it will attract game during a time when hunting seasons are open, however it will generally need to be supplemented with other species that are available at other times of the year. Like nuts, fruits, or soft mast, tend to be a pretty high calorie food source. There are a huge variety of fruit bearing plant species ranging from tiny forbs like strawberries, to massive cherry trees and everything in between. Blackberries, grapes, rose hips, pawpaws, apples, plums, prickly pears and persimmons are all great examples of possible fruit species for your property. Like nuts individual fruit species tend to have a narrow window of availability, but unlike nuts this could range throughout the year. The worst time of year for fruits is generally spring time but even then there are some fruits like rose hips that are able to persist all winter and into spring. I personally have noticed black bears in early spring gorging themselves on the last remaining rose hips and depositing their seeds around my property. So I would say fruits are a must have for most properties especially when focusing on game with omnivore type feeding habits. However I will also note that even browsers and grazers will commonly relish these food sources if available. The last food source I'll focus on are tubers. While for most game species these will not be a food source there are a few that are able to dig such as pigs and bears that can make use of it. Some tubers that might attract game are groundnuts, jerusalem artichokes, camas, wild onions, nutsedge, biscuitroot and cattails. So since omnivores will usually have a very varied diet you can attract them by planting a large variety of species that will attract them year round as well as attract other game species that are usually foliage eaters. And one last thing to point out is that many of the foods you'll plant for omnivores are also great people food and can be foraged for just like the game will do on your property.
Every species of animal will have its own specific nutritional requirements and feeding habits, but many plant species are able to feed a large variety of animals. That's one thing you'll notice when designing a property for wild game is that many of the best plant species will have multiple uses. Not only will they be able to feed multiple game species , but they can also act as great cover as well. And many even have the potential to be great human food sources. So do your research. Figure out what the game animals in your area like to eat and then you'll be able to really start designing your optimal wild game property.