Did poplar prices crash and is it still worth planting now?

Yes, poplar rates have swung up and down over the years. When too many growers planted and supply rose, or plywood demand dipped, prices fell and many were disappointed, then later recovered. This is the nature of any industrial wood tied to one main industry. The lesson is not to plant only because of a past high price, and not to abandon it only because of a past crash. Poplar still has the real advantage that you can grow wheat and other rabi crops between the rows during the season, so your yearly income from the intercrop continues regardless of the timber price, and the timber is a bonus at harvest. Plant good clones, keep the intercropping going, do not over commit all your land to one tree, and check the current plywood mill demand and rate trend in your belt before deciding. Treat the timber as a medium term bonus on top of your annual crop, not a guaranteed jackpot.