Lava question....

[AaronThomas]

Did a rock quarry run recently and they no longer are carrying 1/8 - 1/4 red lava that I use as an amendment for all my trees. So I ended up sifting the crushed lava from the dump truck tracks to get my desired size..... 2 hours for 20 gallons... for 10 bucks I shouldn't complain but... nope not again.
Anyway... when I was done and was driving out I noticed a pile 1/8 - 1/4 black lava. It’s slightly lighter in weight than the red but other than that...
Is there a difference between the two?

 

[MichaelS]

Unlikely there will be much difference chemically - although it's possible. You should first check the pH so you know if you need to make adjustments.
If you are unsure about it's potential toxicity, grow some radish seeds in it (no fertilizer) and check the root tips after a couple of weeks. If they are white, you're good to go.

 

[AaronThomas]

Unlikely there will be much difference chemically - although it's possible. You should first check the pH so you know if you need to make adjustments.
If you are unsure about it's potential toxicity, grow some radish seeds in it (no fertilizer) and check the root tips after a couple of weeks. If they are white, you're good to go.

Interesting... never thought about toxicity in in-organics... was more concerned with break down.
Thanks for the tip!

 

[markyscott]

Did a rock quarry run recently and they no longer are carrying 1/8 - 1/4 red lava that I use as an amendment for all my trees. So I ended up sifting the crushed lava from the dump truck tracks to get my desired size..... 2 hours for 20 gallons... for 10 bucks I shouldn't complain but... nope not again.
Anyway... when I was done and was driving out I noticed a pile 1/8 - 1/4 black lava. It’s slightly lighter in weight than the red but other than that...
Is there a difference between the two?
View attachment 288243View attachment 288244

Almost no difference at all - I use black and red scoria interchangeably. Aesthetically, I prefer the black, but that‘s just personal preference and I use the red if that’s what I have on hand.

Scott

 

[AaronThomas]

Almost no difference at all

Thanks Scott!
Thats great to hear... Will be so much easier to sift and wash.
I totally agree the black is much more aesthetically pleasing.

 

[HardBall]

I heard recently at a club meeting that the red has higher acidity than the black. Does anyone know if there's any truth to that?

 

[Mellow Mullet]

I use both, got a pallet of each for the club last year. I like to mix the two to kinda give it some visual appeal. I am unaware of any different chemical properties between the two colors, the company that I bought it from mines it from the same place. In fact, the red has several different shades, from light to almost dark maroon, and the black has some pieces with a reddish tint.

 

[penumbra]

I like to mix the two to kinda give it some visual appeal.

Ditto.

 

[Leo in N E Illinois]

I heard recently at a club meeting that the red has higher acidity than the black. Does anyone know if there's any truth to that?

Usually the difference chemically between the red and the black makes no significant difference for horticultural purposes.
BUT
It "kind of depends" on the volcano that was the source. Every volcano has slightly different chemistry. In North America, majority of the lava quarried will be from the Cascade range, or the more ancient volcanoes (last erupted more than 10,000 yrs ago) scattered along the Rocky Mountains. In North America most of the lava is "pretty similar" in composition. Rocky Mountains are NOT a volcanic chain, but there are areas with scattered now dormant volcanoes, notably in New Mexico and Arizona, maybe one or two areas in Nevada. Also Idaho has an area where lava can be quarried

I know in Hawaii, Kilauea, Mona Loa, & Mona Kea are shield volcanoes, and a little different chemically from our continental volcanoes. The commercial orchid growers I know there do make a distinction between the red and black lava. But since we never get "imported from Hawaii" lava, I never bothered to remember which was more acidic, and which was less acidic. But in Hawaii they do use the red and the black slightly differently.

 

[sorce]

So you toiled over the "ok" then found the "good" all uniform?

Life!

Sorce

 

[AaronThomas]

dormant volcanoes, notably in New Mexico and Arizona

I believe they quarry sources there material locally... worth a call just to find out. But everything ya'll are saying and everything I have researched states they are basically the same. Perhaps a slight temp difference during the summer but can't imagine that would negatively impact the trees.
Thanks everyone for your input!

 

[AaronThomas]

Life!

LOL yep... figures.
Drove right by the stuff... guess it didn't make sense for them to put the lavas next to each other.
On the bright side my neck got a good tan!

 

[AaronThomas]

I use both

Saw that a few online distributers market both the red and black exactly the same.

 

[Mellow Mullet]

Saw that a few online distributers market both the red and black exactly the same.

exactly, I order mine from Red Hill Lava

 

[62veedub]

Sorry to dig up an old thread, but where is the quarry you went to?

 

[AaronThomas]

Sorry to dig up an old thread

Since you’re in Phoenix I assume you’re talking to me? It’s in Tucson on 22nd.and Pantano. Acme Gravel... Check it out if you’re looking for amendments you can find just about everything you’ll need from pumice to lava to bark.
And I apologize… It’s not really a quarry but a yard

 

[62veedub]

Yeah, sorry, should have clarified!
I was actually planning a trip there for some pumice. Also wanted to check out Mesquite Nursery