Substantial K in rainforest through fall.

[Rick]

But you are saying that all those trials are wrong?

Not for annual food crops that are meant to maximize starch production in a 6 month time frame and get harvested. But I've also looked at trials for thing like coffee and pecan trees those are low K. I've also seen trials for turf grass that are low K high Ca.

The growth rate and production of harvest-able fruiting characteristics of orchids is irrelevant to how to feed cultivated corn and tomatoes.

However neither can you say that a plant fed with a 50/50 N to K (as mine always have been) leads some sort of retardation in growth or whatever.

That's what I thought too until I changed my ways and found out otherwise. As long as you never try it, you won't notice the difference either.

My mounted Phals, Bulbos, Oncidia, Vanda... are doing light years better than by the old 50/50 N to K. And its not just my stuff either.

It's been more than 2 years for me, and I see absolutely no reason to go back to my old feeding regime. Maybe you need to figure out why so many of us are getting better results despite the low K rather than trying to convince us that its just plain old wrong and we need to go back to methods that were stunting/killing our plants.

 

[Rick]

What I'm talking about is the ratios relative to each other.

By that logic we should be able to pot up our plants directly in a jar of fertilizer and they should thrive.oke:

 

[Rick]

trees may be hoarding as much K as possible to compensate.

That Zotz paper on Panamanian epihytes you supplied a couple years ago would agree with this statement in as much as all epiphytic species (and the trees they live on) recycle most of their P and K before leaf senescence. On the flip side there is so much more Ca available in the system to start with, they don't internally recycle hardly any leaf Ca at senescence.

Another point of logic is to explain how obviously healthy in situ orchids generally have higher Ca than K leaf tissue concentrations, and we can't replicate either the growth quality or tissue concentration ratios in cultivation using the high K feeding regime you are advocating.

 

[Stone]

http://www.google.com/url?sa=t&rct=...VtFf-6afvtx9bHQ&bvm=bv.62578216,d.eW0&cad=rja

Here's a link to yet another paper on nutrient flux in rainforest. A high K to Ca ratio in rain water is not universal, and it is a very small part of the picture with regard to total nutrient flux.

Table 6 supports what I'm saying totally. K is usually higher than both N and Ca

 

[Stone]

Maybe you need to figure out why so many of us are getting better results despite the low K rather than trying to convince us that its just plain old wrong and we need to go back to methods that were stunting/killing our plants

.

Well you've been trying to convince me based on your the data you have seen. I have looked at that and taken it on board. However I'm also looking at data and to me what I see here shows me what the plants (especially epiphytes) are recieving directly.(not based on theory) The link you posted says the same thing. In fact it seems you can extrapolate that across the board.


I am simply seeing things and posting. At the moment the only thing I have to go on is your (and others) claim that things have improved with low K. But I also have a million other examples of cultivated orchids grown with high K ratios that would put yours and mine to shame. Surley you can't just ignor that fact and pretend it does not exist. Just google any species and you will see what I mean.

I can't believe that as a scientist you would expect me to just take your word for it without looking at all avaiable material. There could be a million reasons why your plants are doing better but I'm yet to be convinced it is the low K.

K-lite simply does not conform with the throughfall evidence.

 

[Stone]

By that logic we should be able to pot up our plants directly in a jar of fertilizer and they should thrive.oke:

Sorry but I have no idea what that means

 

[Stone]

methods that were stunting/killing our plants.

How come my plants are not stunted or killed?

 

[Stone]

Another point of logic is to explain how obviously healthy in situ orchids generally have higher Ca than K leaf tissue concentrations

,

Because K is much more easily leached than Ca.

and we can't replicate either the growth quality or tissue concentration ratios in cultivation using the high K feeding regime you are advocating.

There could be a gazillion (a lot :evil reasons why we can't replicate growth quality of wild plants. Mostly its probably the environment or technique we are giving them but it could be anything from temprature sequence to micronutrients. Who knows?
And where am I advocating a high K regime? You are advocating a low K regime and I am questioning it.

 

[Trithor]

I love these tennis matches! Bravo! It is in discussions like this that most useful information come to the fore (and a little humour)
Have you ever noticed how it has a faint odour of ammonia in a tropical rainforest in the early morning. (I have never figured out why it is stronger in the morning than at other times)
One factor we don't seem to be addressing is that non-atmospheric elements are there or they are not, and that concentrations wont just change, whereas nitrogen concentrations are in constant flux, the work of the ubiquitous nitrogen fixing bacteria.

 

[Stone]

I love these tennis matches!

Me too but Rick and Lance are playing doubles :rollhappy:

 

[gonewild]

Consider also the location of the sample points for the through fall. The samples are collected at ground level. Most orchids grow far above ground level so ground level nutrient content of through fall water is not what most species are in contact with. When I go out in the forest and look up at orchids in the canopy it appears that the water they receive is mostly from straight on rain or if from through fall the rain has had minimal exposure to the forest canopy.

To me it is obvious that most of the nutrients the plants get are from the moss and lichens and other organisms that surround the roots.
Lichens are known to extract many nutrients directly from the atmosphere and they excrete nutrients for the other plants.

I can't speak for Asian orchid species but most South American species of orchids come from forests that have very little canopy cover if any. Very few species come from forest types that these through fall studies have been done in.

 

[gonewild]

Me too but Rick and Lance are playing doubles :rollhappy:

:rollhappy:

Do you want me to play on your side for a while?

 

[Trithor]

To me it is obvious that most of the nutrients the plants get are from the moss and lichens and other organisms that surround the roots.
Lichens are known to extract many nutrients directly from the atmosphere and they excrete nutrients for the other plants.

I accept that, but, Where would the lichens and mosses get the nutrients from? Unless air is different there from what I studied within my MD degree, elements such as K, P, Na, Ca, Mg, are not part of the atmosphere. Nitrogen, yes, present as upwards of 70% of the atmosphere and in the presence of nitrogen fixing bacteria, can be readily converted to nitrates and ammonia (a process which I am sure lichen is actively involved in, one of the reasons why I was hesitant to compare the K to the N as a ratio in the fall through)
So surely the ratios of not atmospheric elements to each other will remain reasonably constant, but the ratio of N might well change relative to them?

 

[keithrs]

Me too but Rick and Lance are playing doubles :rollhappy:

:rollhappy:

Do you want me to play on your side for a while?

 

[Rick]

Table 6 supports what I'm saying totally. K is usually higher than both N and Ca

Actually Table 6 is Net throughfall (how much is left after hitting the leaves).

The actual precipitation input is in Table 9 which shows about 50% of sites with significantly higher K input than Ca.

But total nutrient flux also concerns transfer through fine litterfall (direct decomp/transfer at the root level) which generally buries the K input from rain input.

You need to look at mass balance. The total sum is represented in Table 2 (above ground biomass). You can't get to the values in Table 2 by only using the values in tables 6 and 9.

 

[Rick]

I accept that, but, Where would the lichens and mosses get the nutrients from? Unless air is different there from what I studied within my MD degree, elements such as K, P, Na, Ca, Mg, are not part of the atmosphere. Nitrogen, yes, present as upwards of 70% of the atmosphere and in the presence of nitrogen fixing bacteria, can be readily converted to nitrates and ammonia (a process which I am sure lichen is actively involved in, one of the reasons why I was hesitant to compare the K to the N as a ratio in the fall through)

There is a little bit of KPNaCaMg in the atmosphere as noted in the rain inputs data from these sites. But the bulk of these materials, especially P, Ca, and Mg, are brought up from the soil by the trees which in turn slough off/transfer via arboreal degraders (bacteria, lichens/mosses/fungi/insects/direct water erosion or leaching). Stone likes to cherry pick the data tables in these nutrient flux papers to find the high K source inputs, but thats only a small part of the total equation of what ends up in the plants.

 

[Rick]

So surely the ratios of not atmospheric elements to each other will remain reasonably constant, but the ratio of N might well change relative to them?

Yes N is independent of the elements generally derived from soils. The arboreal nitrogen fixing capacity in the epiphytic system is fairly impressive. But N from soil degradation and uptake into the trees is also significant.

But getting out of the ratio biz, the total amount of these inorganic nutrients is still just a tiny fraction of the total biomass, and applying these materials at orders of magnitude greater than eco-relevance turned the science into a toxicology experiment.

 

[gonewild]

I accept that, but, Where would the lichens and mosses get the nutrients from? Unless air is different there from what I studied within my MD degree, elements such as K, P, Na, Ca, Mg, are not part of the atmosphere.

It seems that new studies are showing that lichens actually extract compounds from the air and convert them into other compounds that they excrete. I don't have the links to the papers I read but they did suggest that lichens are capable of producing various nutrients for plants from the atmosphere.

Science needs to forget everything that has been published and actually look at the environment from a different perspective. Just because it is excepted scientific fact does not make it correct.... nor are the things we learned in the past necessarily correct.....

Calcium is in the atmosphere...
http://link.springer.com/article/10.1007/BF02607214

Phosphorous is in the atmosphere... http://www.sciencedirect.com/science/article/pii/0016703779901121

 

[Rick]

Here's a summary of the nutrient flux for PNG Montane forest from that article I posted.


Note the huge amount of Ca relative to K tied up in the above ground biomass, and the large amounts of nutrients moved around in the litterfall (also heavy in Ca).

The rainfall input doesn't come close to making a big dent on either the K or Ca, but based on net throughfall K is moving around with the rainfall easier than Ca. But net throughfall doesn't explain whats actually in the leaves and the rest of the total above ground biomass.

And certainly when boiled down to the amount each plants actually recieve per unit rainfall its all orders of magnitude less than what a basic weakly weekly feeding regime offers.

 

[Stone]

Consider also the location of the sample points for the through fall. The samples are collected at ground level. Most orchids grow far above ground level so ground level nutrient content of through fall water is not what most species are in contact with. When I go out in the forest and look up at orchids in the canopy it appears that the water they receive is mostly from straight on rain or if from through fall the rain has had minimal exposure to the forest canopy.

To me it is obvious that most of the nutrients the plants get are from the moss and lichens and other organisms that surround the roots.
Lichens are known to extract many nutrients directly from the atmosphere and they excrete nutrients for the other plants.

I can't speak for Asian orchid species but most South American species of orchids come from forests that have very little canopy cover if any. Very few species come from forest types that these through fall studies have been done in.

None of this changes the ratios