reporter: the fires that burned through california's wine country destroyed most of the crop that eric pearsonvested. not grapes but marijuana. >> this is about an acre in size. >> you had processing in there. >> that's right. you had processing and cannabis for processing in here. >> he began picking up bumper crop, the first harvest since marijuana became legal in california. >> it's very exciting. >> the ceo of spar. he had hope to capture some of the $5 billion expected to be spent annually on legal marijuana in california. last month we toured the new facility where marijuana was being processed and prepared for retail sale. cases of marijuana were stacked along the wall. buzz then wine country went up in flames. >> if it wasn't metal it's not here anymore. >> many of the plantss survived but damages by smoke and ash, they will lose much of their value. >> how much did you lose in this? >> i couldn't tell you exactly at this point. a lot. a lot. >> and he is not alone. there are at least 3,000 marijuana farming operations nearby. the growers association estimates tens of millions have bee

> reporter: the fires that burned through california's wine country destroyed most of the crop eric pearson just harvested. no, not grape, but marijuana. >> this was a 40,000 square foot barn, which is about an acre in size. >> reporter: not just a barn... >> that's right. there was equip for processing marijuana in here. >> reporter: the first marijuana for recreational use became legal in california. >> long days of hard work but exciting. >> reporter: he's c.e.o. of spark, a company that's been running a medical marijuana dispensary since 2009. he had hoped to capture some of the $5 billion expected to be spent annually on legal marijuana in california. last month we toured spark's new sonoma facility where marijuana because being processed and prepared for retale sale. cases of marijuana were stacked along the wall. but then wine country went up in flames. >> if it wasn't metal, it's in the here anymore. >> reporter: many of the marijuana plants survived, but damaged by smoke and ash, they will lose much of their value in the retail market. how much did you lose this this? >> i couldn't

. >> the fires that burned through california's wine country destroyed most of the crop, eric pearsonsted. no, not grapes, but marijuana. >> this was a 40,000 square foot barn. about an achor in size. >> not just a barn. procession in there. >> processing, packaging. >> aroma is great. >> last month pearson began picking a bumper crop. first harvest since it became legal in california. >> long days of hard work. very exciting. >> ceo of spack, running medical marijuana dispensaries since 2009, had hoped to capture some of the $5 billion expected spent annually on legal marijuana in california. last month we toured the sonoma facility where marijuana was processed prepared for retail sale. cases of marijuana were stacked along the wall. but then, wine country went up in flames. >> if it wasn't metal it is not here. >> many marijuana plants survived, damaged by smoke and ash, they lose much of their value in the retail market. how much did you lose? >> couldn't tell you exactly at this point. a lot. >> a lot. >> a lot. >> he is not alone. there are at least 3,000 marijuana farming opera