His reporting indicates that after dropping lower than $1,000 pound ($62.50/ounce), Northern California prices for the latest harvest have now rebounded to $2,000-$2,500 a pound ($125-$156/ounce).
I suspect normal market forces, bad weather and mold drove most of the change. The article suggests that law enforcement was influential as well by leading some growers to cut back on their crop. Possible, but it also led some dispensaries to close, which would have the opposite effect on prices (i.e., fewer dispensaries chasing grown crop would lower prices).
[Cross-posted at The Reality-Based Community]