New flower species - arable weeds

I had cause to dig over some ground in the garden (which is mainly just an extension of the meadows) for the first time this year - firstly to plant a few blackcurrant bushes and secondly to lay an electricity cable underground. Three months later I have a new set of flowers presumably from seeds that have been lying dormant since the last time some ground was dug over - probably a decade or more ago. Fat Hen, Bifid Hemp Nettle, Many-seeded Goosefoot and Lesser Swine Cress have all appeared on the disturbed ground and are all new species to me. If I am right then this is another strategy (certainly for the Fat Hen and the Goosefoot at least) - produce thousands of long-lived seeds and then wait for the ground to be disturbed again. That is why those type of flowers are regarded as pesky arable weeds because arable farming produces exactly the right conditions for them - but every year. Pictured is the Many-seeded Goosefoot (Chenopodium polyspermum).