What?
All Winter Squash (genus Cucurbita), such as Pumpkins, Acorn, and Butternut, are harvested and eaten when the seeds have fully matured and the rind is tough. It’s tough enough to resist scratches from a thumbnail. Winter Squash grow and ripen from long vines and because of their tough skin, they can be stored for a longer duration and into the winter.

Summer Squash (also in the genus Cucurbita), like Yellow Crook-neck squash and Zucchini grow from bushy plants and are generally harvested before the seeds fully mature and while the rind is still tender and soft.

Here is an odd factoid. Watermelons are in the genus Cucurbita and because they are (generally) harvested when the seeds are mature and the skin is tough, they are considered to be a winter squash!

And one more factoid, Cantaloupe/”Muskmelons” are in the genus Cucumis and more closely related to Cucumbers than to Watermelon or other winter squash!

Well, aside from being a superstar at trivia nights, information about plant families can be useful when planning and managing gardens.

Plants that are more closely related may have similar needs or may be susceptible to similar problems. 

For example, Powdery Mildew is a nuisance fungus that grows on the surface of large gourd leaves (plants in the family Cucurbitaceae); it loves relatively humid areas. It is a common occurrence on the leaves of winter squash like Pumpkin, as well as on Cucumbers and Cantaloupe. All of these plants are in the same plant family.

The taxonomic structure is: Family > Genus > Species > sub-species or cultivar/variety.

This is a way of categorizing life by how closely related things are, and it is useful for troubleshooting plant troubles.

For Pumpkins this looks like Cucurbitaceae (Family) > Cucurbita (Genus) > Cucurbita pepo (Species).

For cucumbers, we have  Cucurbitaceae  > Cucumis > Cucumis sativus.

PS. For managing Powdery Mildew. Heavily infected leaves can be pruned out; and in the future, plant your Cucurbits  in a sunny area, avoid over fertilizing, and provide good air circulation to your plants.