To evaluate the expression \(-35v^2\) for \(v = -1\), we first substitute \(-1\) for \(v\):
\[ -35(-1)^2 \]
Next, we calculate \((-1)^2\):
\[ (-1)^2 = 1 \]
Now, substitute this value back into the expression:
\[ -35(1) = -35 \]
Thus, the evaluated expression is:
\[ \boxed{-35} \]