Kitaibelia vol. 6 – no. 1. (2001) p.45-50.
Xanthium italicum Mor. dominálta vegetációfolt fejlődésdinamikájának vizsgálata a Tisza hullámterén
Böszörményi Anikó – Bagi István
Xanthium italicum, common cocklebur is an important invasive non-indigenous species in the Hungarian vegetation. It began to spread in the early 1920s along the riversides. During the 50s it conquered the flood-plains of magnificant tributaries of River Tisza, then it stepped out to the embanked washlands. The agressively spreading X. italicum has become an important plough-land-weed, it forms extended stands in the flood-plains and the washlands.
The study area was located in the flood-plain along River Tisza near Szentes town. Here the X. italicum forms an 0.3 hectare monodominant patch. The X. italicum individuals were counted in squares each 0.5 × 0.5 metre twice a week between 27 May – 3 September 2000. Lenght from the collar to the top of the plant was measured in millimetre and later in centimetre, stem-width between the collar and origin of seed-leaf at the half of the internode in tenth-millimetre accuracy, leaf-number of each individual was counted; lenght and the widht of seed-leafs, which were not withered and fell off, were measured in millimetre accuracy.
The number of individuals decreased from 928 to 22 per square metre during the 101-day-examination, the leaf number increased from 0.43 to 15.6, the average plant-lenght from 3.1 to 104.6 centimetre, the stem-width from 2.0 millimetre to 7.0. (The second data are averages of the last two measures.) Among the measured parametres (with omission the the data of the last measures) the relationship of the leaf-number and the plant-lenght were linear, the stem-width showed exponential growth, while the decreasing of number of individuals was logaritmic taken as a function of time.