The Desert Yam or Bush potato, Ipomoea costata, as mentioned in Hell's Airport and Lasseter's Last Ride, is a fast growing scrambling shrub or creeper with attractive purple pink flowers found across the drier parts of northern Australia, especially the sandplains north of the MacDonnell Ranges, the tubers are prized bush tucker. Coote gives a prosaic account of an unsuccessful yam dig, but Idriess writes nearly two chapters in his best seller on Lasseter's improbable foray into the 'Desert of the Yams' and he attributes this misadventure to the beginning of Lasseter's end.

A long lived and durable perennial, both drought and fire-tolerant and of wayward habit, a nearby Mulga may see the plant climb to five metres or more, lacking support, as an intertwined shrub to a couple of metres, or a ground hugging creeper.  the plant is similar in appearance and nutrient value to the sweet potato Ipomoea batatas. The main tuber directly below the plant tends to be coarse and hard, but the tubers formed on the long lateral roots have a crisp white flesh and can be quite large, from three to 25 inches long, and more than 80% water. Tell tale cracks in the ground above the root system indicate the tuber is ready for harvesting, this can be an exhausting and time consuming exercise, especially if the traditional yam stick is used to unearth the tubers, which may be just below the surface to a couple of metres deep.

On the 30th of July, as the First CAGE Expedition neared the Derwent River, Mickey the Aboriginal guide spotted a wild potato tree, being an Arrente man he would have known the plant as natye and perhaps anticipated a feast. With enthusiastic help from Coote and Blakiston-Houston he started digging for the tubers, but without luck. "both Houston and myself wasted considerable energy following a long root without results", Lasseter would have been a keen observer of this source of bush tucker given his plans to travel alone through the Petermann and Rawlinson Ranges.

Idriess has titled Chapter 26 of Lasseter's Last Ride, 'The Desert of the Yams' a fictitious account of a journey into an unknown desert undertaken by Lasseter and his Aboriginal companions in search of yams, "After the rains the tribe expected a big harvest and they were now yam hungry". It was a near disastrous trek, all the known patches of yams were blighted, apparently by alkaline water. Lasseter and his tribe were now stranded in the desert and likely to perish. The fortuitous arrival of a sick camel, quickly dispatched, saved the tribe but finished Lasseter, the gorge of camel meat and alkaline water caused severe dysentery from which he never completely recovered. Lasseter's journey accounts for about a fortnight of his 78 days without decent food.

Coote gives an indication of the confusion in naming sweet potatoes and yams, "Some people call them yams, but they are not like the ordinary yam, They resemble small round new potatoes, and are more watery than either yams or potatoes", clearly referring to Ipomoea costata and of the same genus as Ipomoea batatas, the widely cultivated sweet potato. the plants are commonly known as morning glories. The true yams are unrelated and from the genus Dioscorea and are a staple root crop throughout  tropical climates, the tubers can be very large, a metre or more long and several kilograms in weight, Idriess would not find yams growing in central Australia, he has used the word in its generic sense and that can include the common potato, genus Solanum and the Taro, genus Colocasia.

"After returning to their more fertile country, the tribe made a quick recovery. Not so Lasseter." no gold, no yams, no hope.

LASSETERIA.

© R.Ross. 1999-2006