  We study the discrete Bamboo Garden Trimming problem (BGT), where we are
given n bamboos with different growth rates. At the end of each day, one can
cut down one bamboo to height zero. The goal in BGT is to make a perpetual
schedule of cuts such that the height of the tallest bamboo ever is minimized.
Here, we improve the current best approximation guarantee by designing a
12/7-approximation algorithm. This result is based on a reduction to the
Pinwheel Scheduling problem. We show that a guarantee of 12/7 is essentially
the best we can hope for if our algorithm is based on this type of reduction.
