What do you call the "unlawful dumping of bulky appliances and furniture"?

I am preparing a vocabulary sheet about the environment for my private students and I am stuck on one expression.

You know when you drive past some fields or in the open countryside and you come across abandoned sofas, washing machines, bath tubs, or rusting vespas that have been left there to "rot"? What do you call that type of rubbish or trash?

It's not litter because that's more to do with discarded crisp (chips) bags, paper, bottles, plastic containers and the like. It's obviously not a landfill because that is the place where all the refuse and waste is taken and then covered with soil. Can I call the act of transporting large heavy goods to intentionally abandon them in the countryside, dumping?

dumping
deposit or dispose of (garbage, waste, or unwanted material), typically in a careless or hurried way.

Is there a more specific term or phrase for this type of vandalism?

Solution 1:

It's called fly-tipping.

The unauthorized dumping of building rubble, household refuse, or other waste, esp. while in the process of transporting it.

– OED

OED has it derived from tip (obviously) and fly n.₂:

2. on the fly: (originally) on the wing, flying; (hence) in motion, moving up and down.

Note that the verb fly-tip is a back-formation from fly-tipping.

Solution 2:

In the UK at least, illegally dumping rubbish, including large items, in the countryside is termed fly-tipping, from the expression on the fly meaning quickly and impulsively.