An Acre consist of 6 plots each measuring 6 x 120ft. Counting one by one the total number of Pineapple stem to fill up an acre of land might be a job for another day.
It depends on the spacing and how you want it to be. I will advice you to just ask around in your area for a place to get stems.
The land is thoroughly prepared by ploughing or hoeing before planting. But on the hills, the land should either be terraced or cut into strips of suitable width by constructing contour trenches with a depth of 45-50 cm and a width of 30 cm. These serve the purpose of catching the surface runoff. Planting is also done on the slopes of the hillocks without terraces etc upto a gradient of 60° across the slope, so that the losses due to soil erosion can be minimized. On hill slopes, only individual pits are prepared for placing the planting material instead of digging the whole area, as it may cause unnecessary soil erosion.
There are two systems of pineapple planting viz, single row system and double row system. Single row system is more common in this region but it is uneconomical and at the same time, fruits develop sunburn in the absence of adequate shade because of low density planting. Double row system is recommended which gives more profits and allows the maximum use of land, less weed infestations, protection from sunburn and lodging of fruits, due to mutual support of plants.
Double row planting is done by alternating two rows of crops by a wider mound or path. For optimum plant density, particularly in the hills. It is advisable to space two rows of crops at a distance of 60 cm, followed by a mound or flat path of 90 cm width. Within the row plants are spaced 30 cm apart. In this way 43,500 plants can be accommodated in one hectare of land. For more info you can use this best essay writing service to having a wonderful assistant in writing and even you can get the guidelines too.