Co2 kill flavor an smell?

[Cerathule]

The trichomes are found at the surface so it's an overtly swelling of calyx and hardening these (ie. by accumulation of nutes) which should prevent this dilution effect. So that could be done by limiting N at some appointed time in flower.
The presence of CO2 enrichment makes it also easier for the plant as it reduces the wasteful photorespiration.

 

[Cerathule]

Too bad the full text is not free.

Strange, your link shows me the full text + .pdf option.

 

[Douglas.Curtis]

I've read studies pointing toward 68F as being the optimal temp for cannabis growth. (Now wtfck did I read that...? hrmmm maybe 5 or 6yrs ago?)

I'm not familiar with the link between transpiration and photosynthesis, if any, but I noticed they stayed with 55% RH for all temps measured. The lowest temp measured was 77F, so also an incomplete study in my view.

 

[Hammerhead]

It's the roots that don't do well in cold temps. I've seen plants in a cold room (70F). I'm sure the roots were colder. Growth had stalled/slowed..

 

[Douglas.Curtis]

It's the roots that don't do well in cold temps. I've seen plants in a cold room (70F). I'm sure the roots were colder. Growth had stalled/slowed..

Indeed, I used aquarium heaters for years to keep my resevoirs at 69F for maximum root health and growth. This temp needs to be higher in soil to reach the same rates.

 

[Cerathule]

I've read studies pointing toward 68F as being the optimal temp for cannabis growth. (Now wtfck did I read that...? hrmmm maybe 5 or 6yrs ago?) I'm not familiar with the link between transpiration and photosynthesis, if any, but I noticed they stayed with 55% RH for all temps measured. The lowest temp measured was 77F, so also an incomplete study in my view.

C3 respiration clears unwanted product (when the acceptor binds oxygen instead of carbon). To keep this error low is the key behind the lower temps or increasing CO2 for C3.
But it seems to be genetically as well as Chandra reported way higher optimum temps for outdoor Sativa of hot climates

Plus, there are many other -mostly metabolic- arguments ranging to the temp discussion. Enough to basically show the answer cannot be given by a single study, or averaging across all the genetic landscape.
Our plant is vastly divers.

 

[hambre]

I seriously recommend some of the idiots who are taking shit personal here to at least listen to Bruce Bugbee, from the Utah State University, there is dozens of studies about this topic. Did you read them? Because I did, and I believe someone as Bugbee before some 70+ years old creep who did nothing more in his life than showing off on a forum. It is disgusting the lack of real arguments from some people. Instead of answering: "yeah, the temperature where terpenes sublimate/evaporate/degrade when growing is thi: (insert temp here), so you are wrong", they show off their supposed "years of experience"... Well... Clearly you have some problem on your house or your relationships (which I doubt you have) and throw your shit here.
It is so easy to give a straight answer, but, no, you have to take it personal.

I wonder what would you do if this is a personal discussion... It is easy on the forums, huh?

It is easier to prove me wrong!!! PROVE ME WRONG! Present EVIDENCE, FACTS!

 

[hambre]

All I see is a 10 year old kid having a tantrums. People like you live on drama. Just another chad ruing discussions. Another person that can't gorw weed well added to ignore.

 

[hambre]

In this article someone posted before (sorry I don`t remember who ATM) https://www.truelabscannabis.com/blog/terpene-boiling-points it says clearly, and I quote: "SOME terpenes BEGIN to evaporate off at temperatures as low as 70ºF, although MOST WILL BEGIN TO DEGRADE AT AROUND 100ºF" end of quote.

So, let me know, who has 100ºF on his controlled growroom?

And, for example, rosin extraction temperatures are around 180-200ºF in COLD extraction, so you lose more terpenes there, and who can say rosin smells or tastes like shit and don`t have any effect on you???
Remember, cannabinoids don`t evaporate at the same rate... So the effect changes drastically. For vaping, the usual recommendation is +-390ºF, does it your vaporizer taste like shit then???

Then, some say LED`s make buds tasteless and the bud lose effect, get yourself right then, look at the contradiction...

Remember, the article talks about PRESERVATION of terpenes AFTER HARVESTED. While growing, higher temperatures STIMULATES the production of terpenes, that is why people lower temperatures adjusting their VPD`s at the end of the cycle. When harvested, curing is at low temperatures and controlled humidity and air circulation, because humidity and air velocity (wind) also takes their portion of the cake when we talk about terpene degradation.

Check Bugbee`s and others studies about this, it is revealing, he talks about how you can improve and optimize the production of cannabinoids and terpenes in your grow without yield being a problem. Even UV spectrum has an influence on this. But... Who am I, right? A nobody hahaha... My God.

 

[Cerathule]

When you can smell it, there must have been some evaporative losses. Sometimes they smell stronger than in other times, it seems to be tight to stronger phases of growth or buckling up. So when they do, is it due to "terp loss" (by overt evaporation) or actually a gain (from increased current production).

For example my small tent here smelled yesterday the strongest, although it has been way colder the last few days. Most plants are finished, they collapsed in weakness. I'm waiting for this special moment to cut when everything feels right.

 

[Cerathule]

Here you can see the relative difference in leaf temperatures for each light-source:

The HPS heats up like no other lamp, thanks to its high thermal radiation (Infra-Red) output:

^ only the peaks between 350-700nm are photosynthetic. All the rest is heat radiation and the reason this technology has stuck at 40% efficiency. So add to that the convective heat from the bulb. There can be no doubt it's hotter esp. when the fixtures use 20-30% more wattage.

The LEDs high visibly light output and efficiency still has great ramifications to the systems that foremostly absorb in these wavelengths: the photosynthetic pigments, with akzessory pigments aiding in the thermal relaxation of surplus energy. We have responses like UVA-induced photorepair (novo-synthese of D1-D2 subunit protein of PS2), SAR that are anti-ROS, adaptations to leaf size & thickness/general architecture, chloroplast displacement, antenna travel... a huge number of abilities to adapt to the light as a means to optimize its harnessing.

 

[GoatCheese]

@hambre
Explain to me how you can smell cannabis in normal room temperature from a good distance.

PS.
I noticed Cerathule already brought this up

 

[Three Berries]

I just got done with an auto, that had high CO2, uncontrolled for the most part but normally between 1500 and 2500 ppm. 100w LED in a 3x3x5ft tent, kept the temp below 75F, VPD with lights on usually 1.10-1.00. Bucket heaters to keep the roots at 72F. Normal off temps around 65F and RH kept below 78% lights off. Grown in FF OF.

The plant at peak flower had very aromatic citrus smell. No filtering and running in the bedroom. Quite sticky but the trichomes took forever to get cloudy. When they did the smell also disappeared for the most part.

I let it go a week past what I should have. I wonder if picking at peak aromatic/stickiness time would be best?