Cannabis Trait Dominance Data

I have come up with a half-baked plan to start collecting trait dominance data. I will begin with my own plants that I am growing right now. It isn’t complicated. I’ll simply make notes about each strain I am growing based on as many observable traits as I can (and perhaps some cannabinoid testing). I’ll then breed F1 crosses, grow them out and observe which traits show up at F1.

Observable traits will be limited to common things like; leaf shape/colour, branching/structure, flowering time, smells/flavours, budding sites/density, height, etc. I will be set up to test CBD so that data will also be collected.

My question is (and I know I have asked before); is there already a source of cannabis trait dominance data “out there”?

If not, then it seems like something a community could build very quickly and more accurately than any individual. A database could be set up to track the data and make it available to community breeders.

Just brainstorming here. I’ll be collecting my own data, but I see much greater potential if many others are involved


It’s multi dimensional data. Between chemotype, genotype, phenotypes, environment, grow methods, seed source. The data modeling necessary to pair two growers observations would challenge me.

Do we know if the dominance of a trait applies across all strains or might they be contingent on other (perhaps epigenetic?) factors? Could broad leaves be dominant with indica configurations, less so in balanced hybrids and recessive at the sativa end of that spectrum?


A very good point! However, if unanimous results were obtained for a certain trait (ex. photoperiod dominance over autoflower) despite all the differences you mention, then that would be even more convincing, not less.

I do not know, but I suspect someone around here does know (and I suspect the answer is that cannabis is a single species (despite the human tendency to divide it into 3 or 4 categories) and therefore dominant traits are dominant across the spectrum).


We could even start with a simple list. Is it safe to say that everyone agrees that photoperiod is dominant over autoflower?

If so, can we begin the list like this?

Photoperiod > autoflower


My basic understanding is that growing conditions should not change whether a trait is dominant or recessive. They can influence the phenology of course, but only within a certain range.

I’m happy to be corrected though. And I appreciate the intention of the thread. If we get all the cool kids on OG to contribute this could grow quite fast.

1 Like

The cool and the brave. People are commonly criticized and mocked for trying to make lists like this.

Someone at Grass City was brave enough to create their own little list:

Tall > short
Early > late
Pinnate leaf > webbed leaf
Green leaf > purple leaf
High THC > low THC(usually high CBD)
Green calyx > purple calyx
Large seed size > small seed size
Diffuse root > tap root


Why? Is the approach wrong? I was wondering (or even asking) about this quite often. But I have not even grown enough to have experienced a fair amount of traits.

1 Like

Honestly, I don’t know why. It is as if there are two main reactions; from those who think it is all way too complicated to even comprehend, and then those who apparently understand (at least some of) this stuff but for one reason or another won’t participate in the discussion other than to say “it’s not that simple, moron”. Perhaps some just want to keep that info to themselves for various reasons.

What I am trying to say is that massive amounts of data can show trends, and we might find a lot of valuable information by just recording all that data into a searchable database. If we find that 998 times out of 100, green leaves dominates purple leaves this is very practical and useful information, even if we don’t all understand why.


A list of traits and whether they are dominant/recessive or incomplete dominance is something I expected to exist already and be easy to find but in some searching I have not found really anything like it. Even just a trait checklist to be able to consistently inventory plants for there traits would be super helpful in making breeding decisions. I have a google doc started with all the leads I find mentioned both for dominant/recessive and just heritable traits that I will be adding to. I will post once I have something worth anything.