At the head of the Humboldt river frosts are of almost nightly occurrence, and in the Carson Valley damaging frosts often occur in June.
It does not, however, prevail for long, and in the first half of September frosts begin on the middle Urals.
Coccinea, often confounded with the red oak, but with larger leaves, with long lobes ending in several acute points; they change to a brilliant scarlet with the first October frosts, giving one of the most striking of the various glowing tints that render the American forests so beautiful in autumn.
While flowers bloom throughout the year at Portland, frosts have occurred in every month of the year at Lakeview, in the Great Basin.
The frosts are severe, the Danube being often icebound for three months.