RIME ICE

We've had several days of very foggy nights with temperatures below freezing.  When that happens, drops of fog (liquid water) land on tree branches (and other things for that matter) and if the surface temperature of the substrate is below freezing, ice is formed.  Ice formed from a liquid state is called rime ice...as opposed to hoar frost which forms when ice crystals are formed from water vapor, bypassing the liquid state.  One can get "frost" on one's automobile windshield from either phenomenon.  In the U.S. this is often seen on house windows and is called Jack Frost.
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The size of the crystal growth is proportional to the amount of fog (water) available, the length of time it hangs around and how cold the temperature is.  The colder the temp, the denser the fog, the longer the fog stays around, the larger the crystal growth will be.
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EXTRA:  Close up of the rime ice crystals.  You can see that the crystals are not particularly large....and now you have the tools to explain that.  Sometimes.....the ice is so thick that the entire countryside looks like a frozen ice panorama....right out of Dr. Zhivago (if you remember the film).  By mid afternoon, the crystals had all melted.  We are right on the edge of weather turning cold and/or getting warmer so this has happened several nights in a row.  Unfortunately, that same ice forms on cold roadways and leads to the formation of "black ice" which drivers cannot see and is thusly responsible for many auto accidents.
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BEST IN LARGE.