Fur is usually implemented as a render effect -- there isn't a 1:1 correspondence with geometry, although geometry may be used to achieve the effect (textured polygonal strips, for example, or the newer and better looking 'shells and fins' methods), so there isn't really anything to export unless you were you convert the fur representation to 3D geometry. This would almost certainly result in extremely poor performance in your game.
The solution you probably want to is abandon using Maya to generate the foliage and employ a rendering effect in your game code to achieve the desired results instead. The article I linked to before provides one possible implementation; here is another example, using XNA.
However, since you said you are using Maya's fur rendering to produce plants, you may instead want to consider rendering algorithms designed for exactly that effect. Game Rendering has a whole section on "vegetation." There's quite a few options for grass rendering, for example:
I know you mentioned being CPU limited, but you didn't specify exactly how much so, or what the GPU resources you have available are. It should be reasonable these days to implement some level of these techniques with reasonable scalability back to older hardware and without too much CPU strain.
If that fails, you can always fall back to using simple polygonal billboard strips and "exporting" your fur out of Maya by rendering it as a texture you eventually apply to the billboards in your game. But actually exporting the fur as geometry is almost certainly not the approach you want.