By default Ubuntu has Trash icon showed on desktop , if we want to remove this icon we need install third party tool like Gnome-Tweak-Tool
sudo apt install gnome-tweak-tool
Then we can run below command in terminal to remove Trash icon
gsettings set org.gnome.nautilus.desktop trash-icon-visible false
Now if you wan to check your Trash , you still can access it via file browser.
If you want to get the Trash icon back to your desktop , you can run below command in your terminal
gsettings set org.gnome.nautilus.desktop trash-icon-visible true