Starting next year, the recreational use of marijuana will be legal in California. But data on the number of plants seized on federal land —where marijuana will continue to be illegal regardless of state law —indicates pot’s black market isn’t going away.


Law enforcement officials say about 1 in 3 marijuana plants grown illicitly in California are on federal land, meaning those farms won’t be legal even after Jan. 1, when new rules on pot grown in California kick in. What’s more, officials estimate they catch only about 1 in 5 illegally grown plants. Last year, the U.S. Forest Service said marijuana growth in national forests in California jumped an estimated 52 percent. The Forest Service also says roughly 80 percent of the people arrested or indicted in cases of illegal marijuana grows in California are from Mexico.

Sites and arrests
National Forest     Sites     Arrests
Klamath                       5             0
Lassen                          10           3
Modoc                          2             1
Six Rivers                    2             4
Shasta/Trinity           52           34
Mendocino                 10           4
Plumas                        23           11
Tahoe                           5              4
Stanislaus                   6              0
Sierra                           21            7
Sequoia                        52           14
San Bernardino          12            1
Los Padres                   27            2
Inyo                               2              0
Angeles                         18            0


The incentive for growing pot is pretty simple – money. Last week, authorities in San Mateo County said they removed some 11,400 illegal marijuana plants, estimating the street value at $22.8 million, or about $2,000 per plant. In 2016, some 1.4 million plants were found and seized on federal land in California –  a street value of about $2.9 billion. Federal estimates suggest the undetected harvest could be five times that amount.


Last year, the U.S. Forest Service and others removed more than 11,000 pounds of trash and 1,250 pounds of fertilizer, plus numerous toxic chemicals, from just one illegal grow site. In all, the Forest Service found 216 such sites in California last year. Some sites are booby trapped, and others are guarded by armed growers, and law enforcement officials say the public should be wary of hiking into grow sites, particularly during harvest time, late summer through fall.

Steven Frick of the Forest Service describes illegal marijuana grows as environmental catastrophes, saying farmers use fertilizers, feces and pesticides – including the highly regulated carbofuran – that wind up “contaminating our environment, including our wilderness areas and wild and scenic rivers.”
There were approximately 80 field agents for 21 million acres of national forest in California in 2016.


Here are some of the Forest Service’s recommendations on what to do and not to do if you encounter what could be an active grow site.


  • Leave the area in the same way entered.
  • Once clear of the site, report your findings to the Forest Service or local law enforcement officials and relay your location and observations.


  • Linger at the site.
  • Call attention to yourself.
  • Touch anything that looks out of the ordinary.


The answer is complicated. Under Proposition 64, people older than 21 are allowed to grow up to six plants. But the rules for cultivation can be regulated – “within reason” – by cities and counties in California. For now, some communities are trying to impose ordinances that some residents are finding overly restrictive, leading to court battles. In the end, it’s likely that cities won’t be able to prevent the personal cultivation of pot, just like they can’t prevent wine or beer collecting or manufacturing. Rules for marijuana farming will remain much more stringent.


Restrictions may apply, and in some states medical marijuana patients may be allowed to grow more if properly licensed.

Source: as of Aug. 27


There are about a dozen different licenses for cultivating cannabis in California. Licensing can range from around $600 to more than $38,000, depending on the size of the growing operation.
A Type 1 outdoor license for up to 50 mature plants will run about $1,185 a year, while a license for indoor cultivation between 10,001 square feet and 22,000 square feet (Type 3A) will cost $38,350. Licenses for operations larger than 22,000 square feet will not be issued until after 2023.
California is implementing a track and trace system to monitor cannabis inventory from seed to sale.

Sources: U.S. Forest Service, DEA, National Park Service

California Bureau of Medical Cannabis Regulation

California Cannabis Portal

U.S. Forest Service