kind of... Here's what you can do. When creating Foliage you can link your brush to a specific layer. So if it's a layer that you already have a weight map for, say a grassland, you can constrain the foliage to that layers weight map. The catch to this is that you are only constrained at the time you are painting in the foliage. So if you decide to change the landscape up later on for some reason, the foliage will not automatically follow the changes made to the weight map.
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... Maybe.