K-lit after 6 months

[Rick]

But K similar to N levels.

At this point I don't think ratios have anything to do with it for N uptake.

Also if you convert conductivity to TDS (by rough standards), and compare to sum of K and N, there's probably more than 50% of the mineral solids unaccounted for in the stem flow and throughfall waters (Ca Mg???)

I have an email into the lead author to see if he has additional data.

 

[Stone]

Ratios are everything. If you took the N out of Klite, you would not have klite anymore but a high K high P fertilizer.

 

[Rick]

Ratios are everything. If you took the N out of Klite, you would not have klite anymore but a high K high P fertilizer.

Don't forget the Ca and Mg:wink:

 

[ALToronto]

Rick, what are the metrics used in the current 'trial'? I use quotes because unless the participants agreed on what to measure and took starting values, there is nothing to put into an ANOVA. Also, large scale observational studies tend to provide too much data, so everything ends up being significant.

I know very little about observational data analysis, just enough to stay away from it. I studied and worked in Design of Experiments, so I'm offering to do what I know.

 

[Rick]

Rick, what are the metrics used in the current 'trial'? I use quotes because unless the participants agreed on what to measure and took starting values, there is nothing to put into an ANOVA. Also, large scale observational studies tend to provide too much data, so everything ends up being significant.

Since the "trial" was never officially defined, some of the best stuff will be based on memory. Few folks (including myself) are keeping detailed records on their entire collections (other than inventory).

Inventory by itself is a decent parameter to monitor. Plants in to program, plants out of program. Exit by death exit by sale/trade/gift. Duration of plant in program. Condition/health, age, size when entered into program.

Then specific program details. Feeding rate, feeding concentration, non-feeding watering rate, chemistry of base irrigation water, potting format and materials, humidity control? temp control? light control?

You can start the "trial" in the future by having each participant select 50 or so plants with matching pre-program plants that are now dead for "before and after" comparisons.

That last point is pretty much what is going on informally now. For instance a typical flasking from Troy Meyers holds about 25 plants. I can go back through my flasking records at TM (which are better than my home records) and count the numbers of seedlings that entered my pre-klite program, and count up the numbers that died vs how many made it to blooming, and compare that to the number making it to blooming now.

There was a post started by Eric Muehlbaur several years ago called "tombstones" showing all the pot tags for all the plants purchased and dead. I have a pretty hefty handful myself. A simple metric would be to count plant tags per year, pre klite and post klite (normalized to total inventory).

There's lots of creative ways to measure sublethal performance too. Leaf length, rate of new growths, total number of leaves per pot, numbers of flowers. Time to first flower, age of new growth to flowering.

You could count things like $ spent on disease and pest control. Frequency of health interventions (normalized to total inventory).

These are all ideas that occur to me while I work with my collection. But since this is my hobby, I just keep the info in my head. If you can get people to write it down or file into excell spread sheets, then you can do stats on it.

 

[Rick]

Also, large scale observational studies tend to provide too much data, so everything ends up being significant.

Actually I find that large population level studies end up with large amounts of noise, and when significant things make it out of the pile, they are slam dunks.

That's the BPJ part of it. Just because something can be statistically significant at a 10% effect doesn't mean you have to accept it as a real effect. It may be arbitrary, but in my biz we don't get serious about things unless they produce 20 to 50 percent effect (like the EC50 or IC25). The NOEC/NOEL is really used these days for QA/QC of the data.

You can increase rep size to find significance at <10% effect, but on a performance basis who really cares about doing 10% better or worse?

 

[Trithor]

My unscientific mind and lack of organisation has prevented me being too formal in my approach. However my need to find an improved fertilizer fomulation for use on my orchids forced me to addopt this very basic approach.
I have 8 benches in my greenhouse, each measuring 1.2m x 2.4m. Each bench has a mixture of seedlings, NFS, and mature flowering size plants. Each bench has a mixture of Parvi, Brachi,Paphio,Barbata, Multis, Complex and near primary hybrids. I tend to distribute plants through the greenhouse in order to try and find 'that ideal' position. I now no longer move them arround since I started my basic trial. I now apply a basic 'balanced' off the shelf formulation to one half of the greenhouse (4 benches) and a K-Lite type formulation to the other half. Before I started I stopped all treatments for a month and only used water to flush the pots as much as was feasible. Now whenever the one side gets fertilizer, the other side gets K-lite. All other treatments are applied to the whole (fungicide, plain water, misting, insecticides etc)
I am now a month into my very basic trial, and can see no difference as of yet. We are of course going into winter and so most growth is slowed. It is my intention to carry on regardless of what I start seeing for a full year (unless I start seeing one half all dying of course)

I would find it too difficult totreat only a few pots any different to the rest without changing a whole buch of other variables in those few pots as well. At present I dont find it inconvenient to treat the whole collection identicaly except a change in which fertilizer from one half to the other. I just have to mix two different concentrates, one for each side.

 

[Stone]

My unscientific mind and lack of organisation has prevented me being too formal in my approach. However my need to find an improved fertilizer fomulation for use on my orchids forced me to addopt this very basic approach.
I have 8 benches in my greenhouse, each measuring 1.2m x 2.4m. Each bench has a mixture of seedlings, NFS, and mature flowering size plants. Each bench has a mixture of Parvi, Brachi,Paphio,Barbata, Multis, Complex and near primary hybrids. I tend to distribute plants through the greenhouse in order to try and find 'that ideal' position. I now no longer move them arround since I started my basic trial. I now apply a basic 'balanced' off the shelf formulation to one half of the greenhouse (4 benches) and a K-Lite type formulation to the other half. Before I started I stopped all treatments for a month and only used water to flush the pots as much as was feasible. Now whenever the one side gets fertilizer, the other side gets K-lite. All other treatments are applied to the whole (fungicide, plain water, misting, insecticides etc)
I am now a month into my very basic trial, and can see no difference as of yet. We are of course going into winter and so most growth is slowed. It is my intention to carry on regardless of what I start seeing for a full year (unless I start seeing one half all dying of course)

I would find it too difficult totreat only a few pots any different to the rest without changing a whole buch of other variables in those few pots as well. At present I dont find it inconvenient to treat the whole collection identicaly except a change in which fertilizer from one half to the other. I just have to mix two different concentrates, one for each side.

That sounds ok to me. What are the details of your two formulations?

 

[Trithor]

I have had two sepparate mixes made for me by the same agricultural fertilizer manufacturer (required quite intricate waltzing to get them to mix my small 25kg of each formulation) I opted to have both mixed by the same company to try and exclude other variables not immediately obvious.
The 'regular' was based on an off the shelf product and has the following;
138g/kg N (NH4=51 & NO3= 110)
130g/Kg P
125g/Kg K
Micro and trace Elements plus red dye

The K-Lite
165g/Kg N
33g/Kg P
16g/Kg K
120g/Kg Ca
10g/Kg Mg
Micro and Trace to same concentration as first formulation plus green dye

It is probably not ideal, but was the best that a carpenter could accomplish with the information at my disposal. I marked plants getting each with the same colour plant tags, my intention is to make notes on these tags when I observe any problems and benifits. Also my RIP box (new one for this study) will allow me to finaly count all the deaths from each group simply by colour of each tag, and to be able at the end to identify what the problem was at the end of my 1 year study.

As I say a very basic study, but I hope to be able to decide which fertilizer works best in my conditions on the range of plants which I grow. Any suggestions will be very welcome

 

[DavidCampen]

Why do you not have any Ca or Mg in your 'regular' formulation? If you had added Ca and Mg then I would expect it to perform as well or better than the so called 'K-Lite'. An even better formulation would be to take the 'K-Lite' formulation and just increase the K.

What is the ammonium/nitrate ratios the 'K-Lite' formulation.

Also my RIP box (new one for this study) will allow me to finaly count all the deaths from each group simply by colour of each tag, and to be able at the end to identify what the problem was at the end of my 1 year study

It would be interesting to know the species of each dearly departed as well as age at time of death and how long it had been in your care.

 

[Rick]

Why do you not have any Ca or Mg in your 'regular' formulation? If you had added Ca and Mg then I would expect it to perform as well or better than the so called 'K-Lite'. An even better formulation would be to take the 'K-Lite' formulation and just increase the K.

At that point he would be using the plain old MSU formulation, which really isn't any different from any other "balanced" feed. Not only would it be "reinventing the wheel." It wouldn't be much of an experiment if both sides of the GH are fed the same thing.

I can't recall if you are using a "pure water" source or local mains supply Trithor. The chemistry of that is important to know. I also don't recall what your intended feeding rate was (either temporal rate or concentration).

 

[DavidCampen]

At that point he would be using the plain old MSU formulation

Yes it would be a lot like the MSU formulation.

which really isn't any different from any other "balanced" feed

I disagree, look at Trithor's formulation that has no calcium or magnesium; there are a lot of what you seem to call 'balanced feeds' that do not contain calcium or magnesium.

Not only would it be "reinventing the wheel." It wouldn't be much of an experiment if both sides of the GH are fed the same thing.

No, the other side would be the 'K-Lite' and now the control fertilizer that the 'K-Lite' is being compared against would no longer be defective.

 

[Rick]

The Cornell study covered all these permutations with a base Ca of 200 mg/L and Mg of 25 ppm

It just never used a K of less than 50 ppm. And only ran for 9 months.

So what would be new?

 

[DavidCampen]

The Cornell study covered all these permutations with a base Ca of 200 mg/L and Mg of 25 ppm

It just never used a K of less than 50 ppm. And only ran for 9 months.

So what would be new?

Nothing with the control formulation would be new. That is the purpose of a control. An MSU like formulation would be a good control. How do you evaluate 'K-Lite' if you don't compare it against a known good formulation as a control?

 

[Stone]

Why do you not have any Ca or Mg in your 'regular' formulation?

Absolutely! any control should be able to supply a similar amount of Ca and Mg as the Klite or it is a futile exersize. The whole purpose is to determine if the very low K is making the difference not the increased Ca/Mg. A sprinkle of 50/50 dolomite/gypsum powder at 1 gram/Lt of mix every 2-3 months will provide this for the non-klite plants Or you must add MgS04 and CaNo3 to your fertilizer but this will increase the N. Also the S content of both should be brought into balance somehow or again it may disguise the true results. In fact all ''macro nutrients'' should be as close as possible except the K. If the control has twice as much or half as much P or N or whatever then the trial would be void.

 

[Stone]

I can't recall if you are using a "pure water" source or local mains supply Trithor. The chemistry of that is important to know.

Rick, I'm not sure how relevent the water is in this case. Firstly, Whatever the water chemistry is, most growers have no way of changing it. Secondly, the same water will be used for both the control and the treated plants so it will still be appropriate to determine the efficacy of the low K. Or are you saying that whether we use low K is dependant on the water we use? If thats the case, then we don't need klite at all but just need to adjust the hardness of the water.

 

[ALToronto]

Mike, water quality is important because the interaction between Ca/Mg and K is important. If you're testing the effects of high and low K, you need to keep everything else the same. Since K-Lite has Ca and Mg added, so must the control fertilizer.

Rick, a control is important in any study. Mike's growing conditions are too different from those of the Cornell study to just use the Cornell results.

This is exactly the problem with observational studies - results cannot be aggregated.

 

[Stone]

Mike, water quality is important because the interaction between Ca/Mg and K is important. If you're testing the effects of high and low K, you need to keep everything else the same. Since K-Lite has Ca and Mg added, so must the control fertilizer

.

I wrote exactly that above

 

[Rick]

Why do you not have any Ca or Mg in your 'regular' formulation? If you had added Ca and Mg then I would expect it to perform as well or better than the so called 'K-Lite'. An even better formulation would be to take the 'K-Lite' formulation and just increase the K.

I get it, you want him to compare MSU to K lite. :wink:

I thought you were advocating comparing MSU to the balanced mix without cal/mag.

 

[TyroneGenade]

There would be a problem starting with deflasked seedlings. There is too much variation of growth between seedlings in the first 6 months.

Hmm... good point but...

How are we going to assess the effect of the K-light over other fertilizers? What are we going to measure? Leaf length---compared to what? Plant mass---compared to what? What is our standard, our starting point? We can measure leaf values of various minerals but that doesn't tell us the plant was bigger or fared better? Seedlings offer us the single most telling bit of data: survival. One of Rick's claims is that the seedlings did better. There is simple stats (log-rank, Kaplan-Meier analysis) to test for significantly different survivals between experimental groups.

In addition, as most seedlings will be mostly the same size (there is no big difference in size between my Mystic Jewel x fairrieanum seedlings) we also have a base-line for measuring growth. After the experiment all the seedlings as simply weighed and we have a measure of growth as well as survival. There are also protocols for the exclusion of outliers in datasets. So the seedlings that are doomed to under-perform can be excluded from the eventual dataset.

Maudiae hybrids are now largely inbred so there is very little genetic variation left in them. Perhaps an inbred species such as Roths? Environmental variation may be large but this is typical of natural populations and, I think, is something NOT to be avoided in biological experiments.

Perhaps several different Paph types should be used? Godefroydae is very inbred... what about charlesworthii and primulinum? Then there is callosum and rothschildianum.

Your organic media point is perhaps more important. Maybe SH may be a better medium for the experiment?

I think we have three important questions:
1. Do Paphs survive better with K-light
2. Do Paphs grow better with K-light
3. Do Paphs flower better with K-light

With seedlings we can have a result to 1 & 2 in as little as 12 months and an answer to 3 in only a few years.