I built my first lilac bow back in '01 or so, and reported my experiences some years later in TBB 4. The wood seems to have taken off since then
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Lilac is my all-time favorite bow wood. Extremely dense, hard and strong. Selfbows around 1" wide at mid-limb pulling 55 - 60# with barely a half-inch of string follow. Tough to season, as every lilac bowyer learns. I never cut lilac during the growing season, as that greatly increases the checking (and compromises the outer growth ring). Then, I reduce the staves to a floor-tillered thickness right after cutting, and keep them, bark-on, in a cool place for the first several weeks of initial drying. After that, I debark the staves to let the wood season in a reasonable time, and move them to a drier, warmer environment. From there on, it's weighing and waiting for EMC to arrive. Following this procedure, I have zero checking on my lilac staves, quite unlike the first several ones.
Tuukka