Ah! This is the best mode of identification. Find the expert in your plant of interest and just ask him/her. Wow, this is a lot easier than figuring it out yourself and surely the “expert” has the answer. However, this resource is not always so easy to locate and “experts” can be busy people too.
An expert can be useful in lots of ways. Often “experts” are people knowledgeable of a particular flora (plants of Michigan, wetland plants) or group of plants (sedges, orchids). There are experts in really large groups (all grasses) or very specific groups (Cantua, a small genus of ten species in Central and South America). Plant identification experts can be ecologists, taxonomists, avid natural history buffs, agricultural extension officers, and more.
So how do you find an expert? Experts are often found at universities and colleges, many times associated with herbaria. They can also be found at state and federal agencies associated with conservation and natural resources. You can also learn a lot from plant enthusiasts associated with your state or regional botanical clubs. Citizen scientists and well-informed amateur botanists are great resources!
What is the criterion for determining an expert? Does an expert have to have a Ph.D.? Not necessarily. Experts come in all shapes, sizes and degrees and…self-professed experts are not always right! So even though an “expert” can be really helpful, you are the one who has to be sure the identification is correct. So always verify an identification using the methods previously described: taxonomic keys, written descriptions, image comparison, and specimen comparison.