De or het glanshaver?

The correct Dutch article is:

de glanshaver

Meaning (Dutch) (bloemplanten) Arrhenatherum elatius (var. bulbosum) (var. elatius), een wilde plant uit de grassenfamilie (Poaceae)

How to use glanshaver

the glanshaverde glanshaver
this glanshaverdeze glanshaver
that glanshaverdie glanshaver
our glanshaveronze glanshaver
your glanshaverjouw glanshaver
every glanshaverelke glanshaver
which glanshaver?welke glanshaver?
a big glanshaver / the big glanshavereen grote glanshaver, de grote glanshaver

Dutch words ending in glanshaver

knolglanshaver

In compound words, the last part decides the article. See the rule

Meaning, plural, diminutive, pronunciation and translations: WikiWoordenboek (Dutch Wiktionary) (CC BY-SA 4.0). Example sentences: Tatoeba (CC BY 2.0 FR).