Scurf makes the skin very ugly, but does not seem to affect eating quality. https://www.gardeningknowhow.com/edible/vegetables/sweet-potato/sweet-potato-scurf-information.htm. It appears that some varieties are more susceptible than others. I grow Diane with no problems, but do get it on Porto Rico. It also likes moist soil with high organic content. Eons ago when I was young, my father would not plant sweet potatoes on any plot That had been top dressed with manure.

No manure, but there was compost.

However, we have had 25” of rain since mid May.

I also wonder if Sand Hill inadvertently sent me contaminated slips.

Next year I’m planting them in an area that has lower organic matter (I haven’t added compost there).

The soil is very well drained, but aside from a brief period in early July, the soil has never really been dry even an inch down.

I’ll use the scurfy ones for a mash. They should last until Thanksgiving at least, right?

They don't last very long.

"I’ll use the scurfy ones for a mash. They should last until Thanksgiving at least, right?"

No. Peel, blanch and freeze them or can them now. Then you can still use them for Thanksgiving.

"I also wonder if Sand Hill inadvertently sent me contaminated slips."

If you think that is truly possible although the odds are quite slim, then they would like to have that info passed on to them. Such feedback helps them ID and eliminate any problems.

Dave

I will contact them.

I’m not sure where else it came from, since this bed has never grown sweet potatoes before this year.

"this bed has never grown sweet potatoes before this year."

Isn't really relevant. Most all soil types can host the fungus Monilochaeles infuscans (along with hundreds of other fungi) in a dormant state at any time. It is the right conditions of soil temps, high humidity, and a vulnerable crop that make it become active.

Dave

Dave, I think that you are somewhat right about fungals being already around, BUT,I raised sweetpotatoes for years without the scurf problem...on the other hand....explain that.

I see things lke this....Where there has not been scurf, you are not likely to have it [except on White Triumph, maybe]. Once you get it, you need to use extra ordinary measures. I feel it usually comes on boughten potatoes and slips.

Next summer will be an interesting experiment, then.

I‘m planting them 50’ away in sandier soil. We will see what happens.

"BUT,I raised sweetpotatoes for years without the scurf problem...on the other hand....explain that."

It isn't just the presence of the crop Wayne. It is the pro-fungal conditions of overly warm soil plus high humidity. Much more common this past season in many parts of the country because of the higher than average heat and all the rain. Most fungi remain dormant except within a relatively narrow band of combined temp and humidity. That's why soil type - its tilth, complexity, and draining ability - can play such a major role in fungal problems or the lack of them even from year to year. As do weather, mulching, and water regimen contribute.

I'm not denying that slips can be contaminated but just as we wouldn't use a scurf infected potato to grow slips on, I honestly doubt a reputable company would supply slips from potatoes that they could easily see have scurf.

Dave

I had much less scurf this year than last year. This year was a little warmer AND wetter.

The thing is ...that I am managing against scurf. Well, I was last year similarily, but I made sure that there was less fresh organic matter in the soil where the sweetpotatoes were raised. The year before some old infected ones MIGHT have been dumped in the manure pile. I also believe that time gave some healing too. It is a must to remove any infected ones from the garden and not return old rotten ones to the compost. Cooking likely kills the fungas...but I don't want to eat the stained skin...I love eating the skins of uninfected ones. Peeling the scurf off is ok, but those raw peelings must be properly manged...microwaved or trashed.

Today, I dug two crowns from another variety, Betty’s.

No scurf, but these three roots are the only ones out of two crowns big enough to even bother with. These plants suffered two weeks of SEVERE defoliation from a groundhog but finally refoliated.

I will leave the rest in the ground until frost To see if they size up any more.

Since they are too small to really be worth eating, are these large enough to be worth saving for propagation of slips next year?

Is there any different way to store them to keep them viable and sproutable by next March? Biggest one is 1.5” wide.