Unless you participate in a plant rescue field trip with a local plant society, the answer is usually no. Taking plants from the wild is almost never a good idea: 1) It is illegal in many areas, and 2) it may do ecological harm.  Native plants and wildflowers that are removed illegally can alter the balance of plants and insects that exist in that area and leave room for invasive species or weeds to take over. The USDA Forest Service offers collection permits on a limited basis. Check with your local District Office for more information.