I'd say the worst part about riding this time of year is the spider webs, although they look really cool on night rides...that is until they wrap around your face!!! My bike and helmet are still covered in webs. I have all my bikes in the house (Molly LOVES this!!!) and this morning when I came downstairs I walked through cobwebs that had branched off of my bike, I guess I had brought some spiders home with me.
Doug is right, the trails are in great shape right now so you need to get out and enjoy them.