TREE BRANCH FALL ANIMALS
The most visible animals photographed on fallen branches are:
slug
snail
millipede
ant
Of these taxa only the ant is a known inhabitant of the branch before it fell. The ant colony was inside the fallen pine branch and came from a considerable height up the pine tree which is several dozens of feet tall.
The other taxa are common as ground fauna on the property and are not found on branches that fell over night Slugs, snails and the millipede and probably the other ant species represented by single individuals are presumed and likely to secondarily inhabit the fallen branches. Fallen branches are an important food and shelter resource for these animals most likely.

Some fungi and lichen are proving to be identifiable by species thanks to expert help. However identifying fungi and especially lichen by visual photographic means alone I am told is limiting. Chemical signatures are important in distinguishing species.
My goal is to begin to count the number of different species per branch community based on what I can discern from macroscopic photograph of surface and underside images.
I am choosing to select a close identification by species from the automated matching system of iNAT. This is NOT intended as a final species identification but is trying to get a sense of different species by identifying consistently at least visually different types ("common name created by IMKaatz for this project as a type ID" or "robot id hypothesis"):
SOME PREVALENT TYPES! I am finding!!! that are difficult to ID:
1) "olive/bluegreen volcanoes" crustose robot hypothesis "Lecanora strobilina"
2) orange jelly Dacrymyces stillatus
3) black button mm sized individuals scattered widely over branches
4) "Lecidea varians" black, brown, red buttons associated on a crustose lichen patch
5) rust/brown crinkle sheet fungus
6) Parmotrema ruffle lichen
7) "white coral" less than 1cm no other structures Physcia sp
8) Physcia aipolia >2cm larger with reproductive structures present
9) Flavoparmelia caperata
10) Parmelia sulcata "Grey Fingers"
11) Orthotrichaceae mosses are rare
more coming soon...
12) Irpex lacteus "Honeycomb Fungus_

Science happens at many different levels - observational to experimental to publishable. More work is done behind the scenes than is published formally. The behind the scenes stuff provides ideas for serious work. I can only work on iNAT projects during my nature break walks because I have a job. If some one wants to pay me to spend more time on lichens and fungi I am available!
Documenting fallen branches and photographing them above and below and regionally along the length of each branch will provide a record of what species are found in tree top branch communities and show any species association of growth.
Some more preliminary observations I have noticed and would love to have some one experiment with follow. I am NOT getting much moss in the treetops, moss hops onto fallen branches after a long stay on the ground. I thought there were no mosses on the tree branches here but today I found tiny tufts of a moss. This moss bunch of 1 cm or so was in a tree branch knot! perhaps more water or nutrients? I also found moss bunches - just one tiny <1cm on in a Physcia millegrana covered branch. This is my hypothesis that species may form communities of a nonrandom sort benefiting each other mutualistically. I also noticed that in some iNAT photographs of Physcia millegrana I noticed a very similar tiny moss tuft species present! so maybe these species have a mutualism. This is why iNAT is so great! Other people can go look! and see! in the arkives!
I also found no polypores on my branches that fell. There are polypores on very old fallen trees here. Again today I found a branch, large diameter of a few inches, that did have several polypores on it!!! COOL!
One working hypothesis is that large branches can obviousy support more species diverse communities that smaller branches hence i use the ruler as a measure to check branch diameter for different species. I will be able to graph that! Again today I found an exception to this rule which is that larger branches have lichen and fungi and smaller ones less so. There are more fallen dead small branches devoid of species (I am NOT measuring this - a control that would be nice for some one else to do - no time to measure branch diameter in everything that falls to the ground). I have a new photo of an end branch of mm diameter with a HUGE foliose lichen growing on it - actually two samples! So lichen can grow large - several cm wide - on TINY BRANCHES! Another exception to the branch diameter hypothesis is that I am finding abundant jelly fungi on the smallest branch diameters!!! perhaps because these are true parasites? and lichen grow mostly on dead branches??? no idea - just a thought.
The largest fallen branch diameters do commonly provide the MOST DIVERSE COMMUNITIES species wise. I had one branch patch (not the entire branch - I am designating communicites perhaps by touching edges of species??? think about it and see what I can measure reasonably) with 4 species: two lichen, one fungi and one liverwort!!!

I am aiming to compare species colonizing: tree falls, chopped wood blocks, brush pile trimmed tree branches and branches naturally fallen directly from trees on 2 acres. I am leaving out preserved treated 4x4 path borders and the house or porch boards since the treatment of the wood change or preclude natural colonization which is what i am more interested in. This will allow me to see if there are different species for these different wood substrates. If wood is the only element necessary for wood-associating and eating organisms to settle on the species distributions should be the same.
I am not seeing any life appearing on cut down branches thrown and piled on brush piles.
The fallen trees are covered with large shelf fungi and moss carpets.
Storm dropped fallen branches in contrast are heavily laden with many different species of lichen, jellies and other fungi i have not found commonly in over ten years of photographing nature on the same 2 acres.
It suggests tree top dead wood is providing a novel substrate and environmental conditions that are nourishing a distinct community of lichen and fungi.
It would be nice to know if any animal species are unique to this microhabitat.
I see lots of springtails on fallen wood but they are very common ion the leaf litter surrounding this material.
I will NOT be rappeling between or climbing up into the trees but it would be interesting!!!

I am finding mostly either no growth on branches fallen or a large community of different species. Are these cooperate assemblages of fungi? How do they interact? I will be posting more photographs of these species dense branches. Is there a succesion of predicatable species that appear on a clean empty branch? Are some species keystone in enhancing these communities maybe by improved water retention? or nutrients?

I am photographing the total fallen branch length via one photograph with a length scale of a one foot ruler.
I think at the present branch diameter will be most interesting and informative, thicker branches might fall sooner or last longer, TBD HYPOTHESIS!.
Thinner branches cannot hold the same size and number of organisms a thicker branch might, TBD HYPOTHESIS!
I need a better ruler, the transparent ruler is not working well.
Scoring notes on approximate FALL AGE of the branch or tree will allow the determination of how time on the ground or on the living tree a community might take to assemble.

My impression to start is that fallen branches have a predominance of lichen, jellies and other fungi on them when they fall and land on the ground. Growth on the branches includes millimeter sized fungi. Often the branch looks very overgrown to the point where the bark is simply not visible. Some key questions of interest that come to mind are: what macroinvertebrates live in these coverings on these dead branches; do they provide food foraging sites for birds; is there weight added to a dead branch by living colonizing growth especially if is holds water which would be the major weight element. So far I have found one springtail on a fallen branch but it looks similar to the predominant species I am currently photographing on fallen leaves, long fallen tree trunks and the living vegetation.
Issues to resolve are whether the fallen branch is from a 100% dead tree or from a living tree.
Comparisons to make can include living things colonizing a fallen tree on the ground left full in tact which I have several that i have followed that have been down for several years on my yard which is my sample territory.