Where are those saplings? and also trees?

Over the last 5 years, I have got a few hundred saplings planted in my neighborhood, out of my interest in greenery and environment. I was comfortable spending my own money for the same. Many of them were planted in the parks, and some by the road side (where there are no overhead electric lines). I used to make sure they were planted only at the onset of our rainy seasons, so that their survival chances could improve and I could depend more on nature for their watering.

My hope was, at least 40 percent of them would survive the various hostile conditions such as freely roaming cattle that feast on the tree leaves, scarcity of rain, construction and infrastructure work, and less than desirable environment awareness level in public at large. Though I have been monitoring the saplings/trees fairly regularly (weekly), I have found that only about 20 percent of them have survived - the rest have just perished - this is despite arranging for tree guards for those trees vulnerable to cattle grazing, watering the trees in case of real need, and preferring trees such as Pongamia (called "Pongai" or "Honge" in South India) that are fairly resilient to hostile conditions and more geographically-suited. I feel disappointed.

This is what I have observed:
-- Some of the tree guards (mainly for non-Pongamia varieties) got damaged by cattle that eventually led to the growing saplings getting exposed to cattle grazing.
-- Some saplings that survived (and came off their tree guard support) and became decently sized growing trees (maybe 6 feet tall) broke off right at the trunk because some cow leaned on them for scratching comfort - yes it happens. The growing tree could just not take the heavy load and gave way from the trauma. Such trees eventually die. Even if further new leaves sprout from what is left of the trunk, they get devoured by hungry cattle looking for tasty food.
-- The civic authority suddenly decided to develop all the parks in our neighborhood (after 10 years since the layout was formed). Development meant - first wipe out the entire park clean, along with ridding the grass and bushes get rid of all the saplings, shrubs, and growing-up trees. It does not matter even if those saplings did not come in the way of a walking trail or something else; Then dump mud, stone dust and such all over. Fortunately, some decently grown pongamia saplings survived this development onslaught. But, a good number of saplings got wiped out. When the development work began, I had politely requested the workers to save those saplings.
-- One or two growing-up trees found cut off at the base of the trunk - effectively killing them. This clearly looked like the work of some people (for what reason they did it, I do not know) - they cannot be the workers  from the electricity service since there was no electric line running overhead those trees. They seemed to be randomly chosen trees. I tried to ask around, but nobody could tell who cut those trees off.

I am still trying to keep my motivation to plant trees from falling below the active threshold level. It seems hard.