Even on this steep hill the chip mulch sticks to the hog mat. These chips are from Heggenes Arboreal Services and are very useful in improving soil and controlling weeds. In this instance, they are used over hog mat but I also use them over newspaper and cardboard for weed control. For a new garden, mulching like this is invaluable for creating new garden beds. Construction sites end up with both weeds and compacted soil. The mulch will solve both problems -- drowning out the weeds and getting the earthworms happily cultivating under the mulch. Using wood chips, rather than bark, saves money and recycles an otherwise unused byproduct of tree pruning. On Whidbey a load of chips (about 10 yards) is $50, or free if it's the public utility pruners creating them along the road right-of-ways. Fox's Tree Service is another invaluable source of chips. And, for tree work, both Jim Fox and Jason Heggenes are knowledgeable and delightful to work with.