Hydromowing is a process of clearing out brush and young trees from a forested area using a hydromower, which has a spinning drum and carbide teeth. Hydromowing is usually done in areas prone to forest fires. The technique clears out a significant portion of the fuel fires need to become major problems.
Hydromowing is a relatively new process. Before the technique was in use, much of the vegetation that needed to be cleared had to be done by hand, making the process much more time consuming and labor intensive. With a hydromower, more areas can be cleared in less time, giving major fires even fewer places to start. It is estimated that hydromowing costs approximately half of what hand clearing does, making it a very attractive option for some land management agencies.
Hydromowers are large pieces of heavy machinery, similar in size and shape to a bulldozer. Carbide teeth are specially treated blades, similar to what may be seen on many saws, especially circular saws. The alloy used allows the teeth to retain their shape and cutting edge longer, leading to a superior cut.
While no water is used in the actual mowing, hydromowing gets its name because the mulch that it creates has a proficient ability to retain water. This helps grass seeds and other desirable vegetation grow back in place of the undesirable species. Often, after an area is mowed, native grass seeds are planted. Further, the mulch can also help with erosion problems often associated with slopes.
Often used in mountainous regions, hydromowing does have some limitations. The hydromower cannot be used on steeper slopes. Also, some environmental groups have questioned the effectiveness of hydromowing, wondering if the heavy equipment used does not do more harm than good on the fragile ecosystem.
Hyrowmowers cannot pick and choose which plants are affected, unlike hand thinning. If a plant is in the path of the machines, hydromowers will take it down. In some cases, this could eliminate beneficial species that a land management service would otherwise leave alone.
Though hydromowing is not a technique in widespread use, it is gaining in popularity, particularly in the western United States. Colorado and California both have implemented the technique in recent years. California, which seems to garner headlines every year for its major forest fires, has a particular interest in the process.