Cucurbits are monoecious; there are separate male and female blossoms on the same plant. The male flowers tend to open first, followed by the female flowers. It is only when both the male and female flowers are open that pollination can occur.
There is nowhere in the Constitution that says that the Congress can subpoena the President of the U.S. or his people. Congress does however have general subpoena powers, but they are not absolutely clear. There are Supreme Court cases that speak to this. They generally limit this to national security type of issues.
The House of Representatives has the power to impeach the president but then the Senate must convict him before any punishment can be handed out. The question remains, what can be done before and after that? The Constitution says that Congress can have tribunals which are inferior to the Supreme Court.