Can someone tell me please what is the reason for planting double and twisted ?

This is interesting! In Fresno CA. I found an abandoned orchard that had black mission and calimyrna planted together. One of each in the same hole. I wonder why?

   Do you suppose the reason is that when the trees fuse together they assume the attributes of a natural trunk that has that much girth?   or is it for stability in a windy location?     or WHY? 

Gene Hosey,Kathleen Black is an exact match to De La Reina.
This is my pix of Kathleen Black,but if you Google Kathleen black fig you will find the original pix owned by Gene Hosey,with the marking of,East Coast figs,and you will recognize it even better because in my pix the figs are a little bloated because of a very rainy climate while they are ripening.
They are the same cultivar trust me.

Edit Note:Here is ,Gene Hosey ,Kathleen Black,with the marking of his nursery (East coast figs)(second pix)
The nursery is closed for a few years now.

 That's good news for me. I have KB and probaly never be able to get a  De La Reina.
 But the DLR MP is yet different, right?

Most likely it is done so you can reduce your time to a fully productive canopy by having both trees in there as well as adding additional support.  the other benifit I can see is if the one tree has a decline you can easily remove it and not have to remove the entire tree but support the one if neccessary and train the tree to bigger canopy without the same downtime as replanting it.  That's is just my thought.

 good thinking !   I didnt think that far down the road.

Hi,
In other crops this is done for pollination purposes.
With figs, I suppose that black mission or calimyrna is attracting the wasp a bit more, and that one helps the other getting a better pollination rate.
In Malaga, could be the same situation or, could in some holes one be a caprifig and the other a fruiting tree ? And for aesthetic purposes they plant all trees two by two ...

Another reason could be different ripening times. That way your plot produces over a longer period.

I'll try this with a couple figlings that are growing strauight up without laterals.    Will the 2 trunks fuse together like a graft and become one? or can one die without killing the other?   hmmm, co-joined twins..

I would be concerned about mixing of possible different FMV strains...not sure if that is a valid concern or not

Herman2, according to Pons' book DLR is a very productive variety.  On the other hand KB certainly starts out slow with respect to productivity.  Mine is finishing its 3rd season with no ripe figs (though it was heavily damaged by the winter last year).  When it is fully mature would you say that it is very productive?

I doubt that KB and "De la Reina" are the same variety.
As Rewton says, De La Reina seems to be very productive, on the other hand, I don't know any fig less productive than KB, I will remove my KB. After several years in ground, no figs so far!!

The only answer I have gotten from people who twist fig trees together is the Space Issue.
But for farms mixing varieties...I have no clue... why would they mix varieties into one? I know space is not the issue. :/

*I just read another response from an expert fig farmer in Mediterranean. They use wasps, so, wasps pollinate Female (edible) figs to improve the quality. Most farmers mix Capri to Edible in one hole. There is NO problem in Overcaprification (according to farmer's experience).

Soni,
I think we got the answer to your question :)

Looking at the picture where the figs are on the ground, now I know why I can't stand dry figs...Chewing sand in dry figs has never been my fav thang.

Overpollination of figs will lead to splitting and quality problems from what I have read so farms are not tending to too many caprifigs in their orchards so they do not over pollinate.  I have heard nonetheless that some farms will graft a couple branches of a caprifig onto their tree so that each tree will get pollinated without needing to string caprifigs in them.  

This is only from what I have read and I have no first hand experience myself.

Chivas,
I had read that too that's why I asked him about the amount of capri figs.
 
Maybe it's not all trees that are paired with Capri.
Francisco may verify this info, he's is pretty knowledgable. 
I'm not an expert on this subject either but learning.

To my untrained "new to figs" eyes in photos;

De La Reina looks very similar to black mission, KB and NCD. 

Is it possible that these varieties are closely related or are the same original fig ( De La Reina) but have now evolved slight differences due to time and location?

Answering to Rewton:
Your Kathleen black is not very productive because it is not in the ideal climate for such cultivar.
And it might not be in full sun too.
Plant De la Reina in the same climate,and same conditions and it will do the same. 
Mine is also planted in a spot with about 8 hours of sun and ,if i do not pinch it extensively it will not fruit.
This year after being dead to soil line ,it grew ,for 7 foot tall,because it was not pinched as i was not home and surprise:
It did not fruit at all.
I have a neighbor (one miles away) originally from Spain and I gave him a small plant 2 years ago,and planted it in full sun,after I choose the spot for him. It died to soil line too.
It had 30 ripe fruits till now and many more are getting ripe every day.But of course he pinched the tree continuously keeping it no taller than 4 foot.
If you do not believe me ,Rewton,I can get you in contact with him,so you can see for yourself.

My De La Reina (MP) is a young tree. It produced just one fig this season and it was excellent. Very impressive for being the first fig from this tree. I took photos of the dominant leaves from my tree. I'm sure that more variation of the leaves will occur as the tree matures. 
Perhaps we can compare the leaves with those on the KB to see if they come close to a match. I hope that this helps. My DLR (MP) is from a very reliable source.

     

great looking Spanish fig you have there

Herman, my KB is in an excellent spot for sun - at least 8 hours per day. However, to be fair to my KB I don't think I have really given it a really good chance yet.  It was rooted mid summer 2012 and planted in the ground in April of 2013.  It grew very vigorously that summer.  I didn't pinch it heavily and it set a lot of figs actually, but too late to ripen.  Then it froze nearly to the ground last winter.  The new shoots didn't set nearly as many figs but that is probably a good thing since they have no chance of ripening anyway.  I'm going to give it another year or two before making any rash decisions.  Clearly it can do well here since I am only a few miles away from Gene's tree at his old place in DC.  Anyway, it sounds like Axier grows both De la Reina and Kathleen's Black and believes they are different.  I agree though that it seems like they have a lot in common.

Yes Leon They are same type of leaves except mine do not show any Fig disease on leaves,and so leaves are much larger,and stronger because the fig is old and it rains a lot here ,compared to your place.
Same rose ,to pink leaf peduncle same pink growing tips.
When my tree was young the first year after rooting it had the exact leaves like yours,but now leaves are much healthier.
Edit Note:As I said before it grew 7 foot this very year,mostly due to rainy climate.
Will get pixies tomorrow,and post here.
Edit Note;
Here are the pixies of Kathleen black ,now.

I agree look very similar and dlr is not a late fig I think which is also similar. dlr could b similar by chance tho but different DNA but who knows. I've seen one of Genes old trees of KB in summer 2013 and 2012 and it was fine on production. The tree I'm speaking of covered I think 15 to 20 feet diameter canopy. Once mature no major issues with production it seemed. Not saying it was super productive, but seemed about average productive.

They are very close, I agree, but to say that they are the same, I don't.
The fruit is close to "Albacor Comuna" or even "Black Mission", but they are not the same.
Montserrat has much experience and a very professional method to identify his figs and I trust him completely.
He says that De la Reina MP is originated in a very small and isolated village of Majorca.
Can anybody explain how DLR MP arrived to USA decades ago?
Because if I am not wrong, KB was discobered years ago to fig collectors by Gene, who found the fig from an elder woman and from an old tree in USA.
I see a VERY inprobable connection between DLR and KB.
By the way, I am sure that DLR Leon's source and mine are the same, and my DLR grows healthy and like weed, the ethernal song of FMV...