The most common and most likely answer to this crossword clue is the 7 letter word TUSSOCK
I've seen this crossword clue in The Times
T
U
S
S
O
C
K
More clues leading to the result TUSSOCK
- Clump of vegetation seen, jumbo part circling island to the west
- Thick grass stuck out, twining round thus
- Tuft of grass son thus dropped in food
- What stands up like this out of hot footwear?
- Bit of grass scouts lost on summit of Kilimanjaro
- Struts, oddly missing foot-warmer — it makes you clump
- In a bunch, so unable to take hard hit
Buddy explains!

The straight part
We know that "What stands up" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case what stands up = tussock.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TUSSOCK mean?
TUSSOCK noun- A tuft or clump of green grass or similar verdure, forming a small hillock.