Karamürsel Su olive: characteristics, oil content and growing areas

Karamürsel Su has the largest fruit on the list: only 140 per kilo. For comparison, Kilis Yağlık runs to 560 — one Karamürsel Su fruit equals four Kilis fruits.

Karamürsel Su in numbers

Source: Efe, Soykan, Cürebal and Sönmez (2016), Zeytin Kitabı. Fields the source leaves blank are shown as "—"; nothing has been estimated.

What the largest fruit is good for

At a measured 9.44 g, Karamürsel Su sits above Domat — the second largest in the same trial at 7.96 g — and is nine times the 1.09 g of the Arbequina IRTA-18 clone.

In table olives, size is price directly: as the calibre falls, so does the price per kilo. In the buying prices published by Marmarabirlik the gap between 18 fruits and 41 fruits to the unit is more than threefold — see the economics of calibre.

But size alone is not enough. In table processing the flesh-to-stone ratio and how easily the stone leaves the flesh also decide the outcome, and here the table carries a warning: Karamürsel Su also produces the trial's heaviest stone (1.50 g). Its flesh-to-stone ratio of 5.29 is good, yet below Manzanilla at 5.50 and Çilli at 5.57.

One further distinguishing feature is shape: with a shape index of 1.60, Karamürsel Su is the only elongated cultivar in the trial. All the others were round or oval.

When flowering shifts into February

The measurement study recorded another finding: in mild winters, flowering in Karamürsel Su and Domat shifts into February.

This is a concrete example of how climate change shows up in olives. Early flowering carries two risks: a late frost can strike the blossom, and if flowering no longer overlaps with the pollinator cultivar, fertilisation fails.

A chilling requirement of 526 hours places the cultivar in the middle group — below Gemlik at 600 hours and far below the 1,000 hours reported for Ayvalık. More on this: chilling requirement in olives.

What being a Marmara cultivar means

Karamürsel Su is one of the local cultivars of the Marmara region. Because the region's olive growing stands in the shadow of Gemlik, these cultivars are little known — yet Marmara holds real variety beyond Gemlik: Karamürsel Su, Samanlı, Eğriburun and Edincik Su.

On the region's olive growing and its price data: olive growing in Marmara.

Where it stands among measured cultivars

Its position on each axis is shown live in the comparison strip on this page, against every cultivar with a published figure. For the full ranking — and how that ranking is built — see olive variety rankings.

In short

Karamürsel Su is among Türkiye's largest-fruited varieties (140 per kilo) and, at 87% flesh, a pure table olive. It is the local variety of the Yalova–Karamürsel belt and little planted elsewhere.

Despite rivalling Domat on size it never matched it in stuffed processing, owing to differences in skin and texture. For the regional picture, see olive growing in Marmara.