. >> reporter: business for nicholas crawford is booming. >> we've had a lot of tree failures, branch failures, in this case an entire tree falling. and mostly because of the storm. >> reporter: as an arborist, he's seeing a record number of trees like this 60-year-old monterey pine come down. as the homeowner, jeff logan had only one thought. >> thank god for gravity. >> reporter: heavy rain saturates the soil deeply. tree roots cannot stay firmly planted in the ground. >> we like the trees. they create a lot of atmosphere for us. we like being on the edge of glen canyon. but we've been concerned about these particular trees. >> reporter: that's because they have a lot of end weight, where the branchs and trees are mostly on one side shifting their gravity. >> those are all heavily leveraged. they're more likely to come over. >> reporter: homeowners must assess their trees. >> if you notice something going on with your tree, it's important to jump on that right away. proert older trees are a problem, and independent heavy trees are a problem. arborists have given us a list of things