Thanks to everyone for your kind comments. 
I will tell you about the harvesting I did and the extraction I am doing with the grass.
The second time I visited this spot I choose a patch of grass and harvested it by cutting the grass almost to the ground. I harvested it in the afternoon at 4:30 pm. After that the grass was lying in my car for a few hours (not optimal but good enough for first time). When I returned home late in the evening I removed the leaves from the stalks (supposedly the majority of alkaloids are in leaves) and removed the flowers as well. Many very very small seeds fell from the flower/seed heads from handling it. I cut the leaves with a knife into smaller pieces and weigh the semi-wet material. The weigh showed 140 g. Enough for the first time to get to know the grass.
Then I put the leaf material into a stainless pot and covered it with water and added citric acid. I left it like that overnight and began cooking it in the morning next day. The steps I did are basically the usual A/B approach. I did three water extractions with citric acid and with every next pull I tried to cut the leaf material into smaller pieces with scissors. I combined the pulls and reduced the liquid where I felt it's not too much - that was at 800 ml of liquid.
I put the liquid into refrigerator and did decanting and filtering on the liquid. All together quite some gunk and fat (though some fat still remained) came out of it, which was discarded. At that point the acidic tea attained a very deep amber color much like MHRB tea.
At that point I was thinking, if I should base the tea and proceed to extract with a NPS, or maybe do a little experiment and do a MANSKE on the liquid. I decided for the MANSKE first, since I can still base the liquid after that and extract with NPS, so I have nothing to loose.
I added 30g of NaCl (sea salt) to the very hot liquid (800 ml). To my surprise almost immediately after adding the salting something began to precipitate out of the solution. In the morning next day when everything settled I decanted the liquid and saved the unknown powder for further investigation.
Before I was thinking that maybe the possible beta-carbolines in the grass may fall out of the solution that way. Another thing that could happen is that sodium citrate will fall out of solution since I used quite a lot (most likely too much) citric acid in my water extraction. I still have to dry this mistery powder and at least taste it on the tounge to get some crude idea of what it is.
The next step was to base the solution with NaOH (lye). I was not expecting any observable reaction to occur, but it actually did happen in a very similar way when basing MHRB water extract. The solution now became blackish in color and smells very interestingly. The basic solution had to wait for few days in the refrigerator since I had to clean my solvents of any possible residual DMT and mescaline.
Today I started to extract half of the liquid with naphtha. The other one I plan to extract with toluene and compare the results.
I will keep you updated on how the extraction proceeds. I am myself very eager to see what hides in there.
Also I returned to the post exactly a week (7 days) after harvesting the grass patch. You can see that in the pictures below. What happened is that not much new growth appeared - less than I was expecting, however I immediately realized that there is very little nitrogen available in the spot so it is only logical that the growth is slow. When harvesting at home in pots lots of nitrogen is added to get as much new growth as possible - however not the case on that spot.
I will return to the place again to observe what is happening, document it and keep you updated.
Triglav attached the following image(s):
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(5,691kb) downloaded 169 time(s). 2.jpg
(5,022kb) downloaded 168 time(s). 3.jpg
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