[imadoofus]

spurr makes an extremely relevent point.

however, simplicity is the universal language regarding side-by-side. for, its NOT only the method, but the RESULTS.

we could forever intricate the varibles and controls, in the end, the results speak for themselves. i do not see this as a ''definitive'' conclusion to the black holes masked as unknowns, rather, a chance for the community to act as a collective of observations validated through REPEATED examples.

no matter where you start, that is always the beginning ; )

i am enthralled about the new science themed sub forums. if we could all agree on anything, as a community we know too much about too little.

[spurr]

Originally Posted by Sleepy

there's more to it than:
"show me this vs. that"....

it takes a bit more than providing a link to a thread, that is why this forum is set up the way it is...you submit the thread, and it will be examined. then approved or not.

i am happy to post or move threads into the new forum, but they have to meet the criteria set forth in my opening post.

i hope it is not too confusing.

I very much like how you plan to vet the side by sides, very wise of you! I look forward to seeing what you do. Maybe posting a bit of info about how the scientific method works (not in regard to variables like I wrote about before, but in regard to planning and evaluation of experiments) might be useful? Anyway, I look forward to what you do with this sub-forum.

[spurr]

Originally Posted by imadoofus

spurr makes an extremely relevent point.

however, simplicity is the universal language regarding side-by-side. for, its NOT only the method, but the RESULTS.

we could forever intricate the varibles and controls, in the end, the results speak for themselves. i do not see this as a ''definitive'' conclusion to the black holes masked as unknowns, rather, a chance for the community to act as a collective of observations validated through REPEATED examples.

no matter where you start, that is always the beginning ; )

i am enthralled about the new science themed sub forums. if we could all agree on anything, as a community we know too much about too little.

I agree with what you wrote, I was only trying to point out some issues people often overlook. And I wholeheartedly agree with premise of what I bolded in your post, I think about that often: the more I learn, the more I realize there is to learn.


"The more you learn, the more you realize how little you know..." - attributed to Socrates, by Plato (unconfirmed)


"The more you know, the more you realise [sic] how much you don't know - the less you know, the more you think you know" - David T. Freeman

[VerdantGreen]

big up to sleepy! - this forum should become a really useful resource for growers

spurr you should post up some achievable/affordable ways of reducing errors and variables.

[spurr]

Originally Posted by VerdantGreen

big up to sleepy! - this forum should become a really useful resource for growers

spurr you should post up some achievable/affordable ways of reducing errors and variables.

I could do so, if people are interested. Off the top of my head:

(1) controlling or at least measuring Air-to-Leaf Vapor Pressure Deficit with canopy temp and RH (excluding leaf temp) is very easy and cheap. It is important because VPD has a very large affect on many side by sides and has a direct affect upon rate of photosynthesis, water intake and release (transpiration), Ca and Bo uptake, Co2 fixation, yield, etc.

(2) controlling or at least measuring light intensity (irradiance) with Lux is pretty cheap and easy. Albeit not the 'best' method for plants, but it's better than watts/ft^2 and foot candles. Ideally we would use PPFD but that costs $200-300 for basic level quantum senor with data reader.

(3) soil-moisture status in terms of moisture content of soil and soilless media. It is easy and cheap to measure and control if using a moisture meter, albeit a moisture meter is not the 'best' method for plants or microbes, but it's better than using a finger to gauge moisture (which is a total fail). Ideally we would use water tension but that costs ~$100 for a tensiometer.

Those three factors have a very large affect upon the outcome of side by sides (dependent upon the goal of the side by side of course), and IMO, should be at least measured and listed. There are other things worth mentioning, but for now, those are probably some of the most key variables.

Just my 2cents

[Scrogerman]

It must Bug the hell out of all the good people on this site, it seems of late alot of people(None here that i can see./or very very few) think they are the lords of ganja growing & if nobody agrees with them all hell is let loose on the rest of us to put up with.
Peeps should just come to the site, Give their Observations & results & leave it there, then everyone can make up their own minds as to whats right & what is wrong, the way its always been & should be.
I constantly see educated & most experienced growers like Spurr, DG etc etc etc, getting contridicted by people that know barely anything of what they speak, its so annoying & wrecking this site. Im soo glad we now have a forum that should put an end to this bullshit. All we can do is obsearve & relay information. Everyones situation is different & that magic word 'variable' plays a massive part, to us all!
This thread/Concept rocks & i hope we can all get along & learn/teach together, afterall we are supposed to be a community of friendly growers with similar intersts in mind. i say lose the senseless attitude & become as one! 'ICM=1 Family', & we should all stick together. I like a good argument but as long as its done with decorum/sensibility, respect & with decent manner in mind! The Future is bright afterall!

[oldog]

Science forever ! Away with BS ! Your pet theory has to
pass the test. I am done with ezcloner type reproduction after I
stuck two left over cuttings in some dirt at the same time and they are twice the size of their brethren that came out of the cloner after a few weeks.

[foomar]

rate of photosynthesis (Pn)
chlorophyll fluorescence (ex. another method to measure Pn)
irradiance (i.e. PPFD; Photosynthetic Photon Flux Density)
level of Co2
Co2 fixation
level of active rubisco
Air-to-Leaf Vapor Pressure Deficit
sol-water status (i.e. water tension in soil and soilless media)
tissue assays (ex. for level of nutrients like N, P, K, etc).
etc.

There is no way i can afford or justify the cost and time involved with this level of quantification , like to experiment and document but not if its pointless.
Possibly the choice of test plant would be of more effect than some of these figures in the real world.


Have done a few trials in this amateur way changeing only one nute factor at a time.

Same compost from bulk , same for water and base nutes.
Identical clones from a well worked plant.
Light source equally split over two groups , plants rotated and swapped over to even out any minor variations in light level and ventilation.
Result in dry weight in this easy case.
Same experiment repeated back to back with similar results under colder room temps.

Would results obtained in this limited way be of interest or dismissed ?

[LIFEISGOOD]

I love it, our growing community takes another big step in the right direction.

[spurr]

Originally Posted by foomar

There is no way i can afford or justify the cost and time involved with this level of quantification , like to experiment and document but not if its pointless.

Those are only some examples of things that affect the outcome, and things to measure. I was merely trying to point out that a simple side by side should not be regarded on par with a well designed and anally carried out scientific experiment with lots of analytical tools.

Your efforts would not be pointless, not at all. Just try to measure and control everything you can.

This post of mine (here) is a good example of few inexpensive and easy measurements of important variables. If you don't control them, then at least measuring and listing them is a good idea. If you don't it wouldn't make your work invalid, however, including the data makes your work more robust and provides more insight; especially important it is makes repeating of the side by side easier and more accurate.

I was not trying to imply well thoughtout and carried out side by sides are worthless. Far from it, they can be of much value, especially if they are repeated and the same results are found again.

Originally Posted by foomar

Possibly the choice of test plant would be of more effect than some of these figures in the real world.

I do not understand your logic to that statement, can you elaborate? Regardless of the race or variety or cultivar (aka strain), those factors and others have a strong affect upon outcome. But that isn't to say if you don't quantify them your side by side is of no value.

Originally Posted by foomar

Have done a few trials in this amateur way changeing only one nute factor at a time. Same compost from bulk , same for water and base nutes. Identical clones from a well worked plant.
Light source equally split over two groups , plants rotated and swapped over to even out any minor variations in light level and ventilation.

That sounds good, better than lots of side by sides I have seen in the past, the changing of a single variable is key.

Originally Posted by foomar

Result in dry weight in this easy case.

If people use dry weight, it's very important (IMO anyway) to find the average moisture content of a good representative sample of bud. Then subtract the moisture content (as weight) from the total yield. That way the dry weight is really dry weight, and water weight is not included. This will make the results of the trial much more accurate, but especially important is it makes your yield/outcome much more accurately comparable to other growers who may have buds of more of less moisture content. Basically it levels the 'playing field'.

I can write up a super easy method to measure moisture weight, and then how to subtract it to find true dry weight. And it costs nothing if people already have an oven or microwave they can use.

Originally Posted by foomar

Same experiment repeated back to back...

I think you brought up a great point. Repeating the side by side twice, without changing any variables from the first side by side is a great point. That allows a grower to see if something funny is going on by verifying their second side by side results against the first side by side; when both side by sides were done exactly the same each time (this is why measuring the things I listed here is a very good idea, for the sake of repeatability).

Originally Posted by foomar

Would results obtained in this limited way be of interest or dismissed ?

I for one would be interested, you seem to have a solid grasp on how to do a good side by side, esp. if you can measure and report VPD, light intensity (as lux) and moisture content of media (if using soil or soilless).

But, it's up to Sleepy and he seems to be very 'on the ball'; I'm just putting out my 2cents.