adj. Of or pertaining to a dead fuel particle with a timelag of one hour.
Fuel particle timelag is based on the amount of time necessary to lose or gain 63 percent of the difference between the initial moisture content and the equilibrium moisture content at a constant temperature and relative humidity. A 1-hour timelag fuel particle adjusts to changes in equilibrium moisture content on the scale of hours to a day.
Dead fuel particles with a diameter less than 0.25 inch are considered to have a timelag of one hour. Examples of one-hour timelag fuel particles include fine twigs, dead herbaceous plant material such as grasses, and litter.