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We assessed natural regeneration of longleaf pine (Pinus palustris Mill.) using the data collected from the Escambia Experimental Forest in southern Alabama. Fifteen years after the regeneration control, natural regeneration of longleaf pine remained patchy across a wide range of site and stand conditions; slightly more than half of all plots contained regeneration, but the density of seedlings and saplings varied significantly. The abundance of seedlings [less than or equal to] 1- year-old was positively related to stand age and time since last fire, but negatively related to overstory basal area. The abundance of seedlings and saplings was positively related to stand age, but negatively related to time since last fire and overstory basal area. The probability of achieving at least 15 000 seedlings * [ha.sup.-1] that are older than 1 year but less than 1 m tall and at least 1250 saplings * [ha.sup.-1] that are over 1 m tall was, respectively, positively related to the ratio of time since last fire to overstory basal area and the ratio of quadratic mean diameter to site index. A longer fire interval (> 2 to 3 years) should be adopted to naturally regenerate longleaf. We did not find clear zones of exclusion present in natural regeneration even though overstory trees, seedlings, and saplings tended to be repulsive spatially and >80% grass stage seedlings and saplings occurred outside tree crowns. Key words: longleaf pine (Pinus palustris Mill.), natural regeneration, zero- inflated negative binomial model, point pattern data, spatial analysis. Nous avons evalue la regeneration naturelle du pin des marais (Pinus palustris Mill.) en utilisant les donnees recueillies dans la Foret experimentale d'Escambia situee dans le sud de l'Alabama. Quinze ans apres une inspection de la regeneration, la regeneration naturelle du pin des marais etait restee irreguliere malgre une large gamme de conditions de station et de peuplements; un peu plus de la moitie des placettes etaient regenerees, mais la densite des semis et des gaules variait considerablement. L'abondance des semis de moins d'un an etait positivement liee a l'age du peuplement et au temps ecoule depuis le dernier feu, mais negativement liee a la surface terriere du couvert dominant. L'abondance des semis et des gaules etait positivement liee a l'age du peuplement, mais negativement liee au temps ecoule depuis le dernier feu et a la surface terriere du couvert dominant. La probabilite d'obtenir au moins 15 000 semis * [ha.sup.-1] plus vieux qu'un an mais d'une hauteur egale ou inferieure a 1 m, et au moins 1250 gaules * [ha.sup.-1] d'une hauteur superieure a 1 m etait, respectivement, positivement correlee au rapport entre le temps ecoule depuis le dernier feu et la surface terriere du couvert dominant et au rapport entre le diametre quadratique moyen et l'indice de qualite de station. Un intervalle de feu plus long (plus de 2 a 3 ans) devrait etre adopte pour regenerer naturellement le pin des marais. Nous n'avons pas trouve de zones claires d'exclusion de la regeneration naturelle meme si les arbres du couvert dominant, les semis et les gaules avaient tendance a etre spatialement repulsifs et que plus de 80 % des petits semis et des gaules etaient etablis hors de la projection de la cime des arbres. [Traduit par la Redaction] Mots-cles: pin des marais (Pinus palustris Mill.), regeneration naturelle, modele binomial negatif a exces de zero, donnees par patron de points, analyse spatiale., Introduction The longleaf pine (Pinus palustris Mill.) forest ecosystem in the southern United States is a unique ecological community that has experienced a drastic reduction in area, from approximately 37.2 [...]

Swamp titi (Cyrilla racemiflora L.) is a vigorous native shrub or small tree found in poorly drained areas of the southeastern U.S. Coastal Plain. In the absence of fire, it creates dense thickets that prevent herbaceous groundcover in ephemeral wetlands, degrading habitat for uncommon and endangered amphibians and other genera. In our study, aquatic herbicides and methods of application were examined at two forests in north Florida for restoration of ephemeral wetland habitat to benefit wetland‐breeding amphibians. Glyphosate, imazapyr, and combinations of glyphosate and imazapyr were tested in four study protocols that included an operational standard (triclopyr), treatment method control, and untreated control where appropriate. Results of foliar protocols (targeting rootstocks less than 1.5 m tall) demonstrated that glyphosate provided better titi control than imazapyr (average of 79% vs. 12% mortality), there was no strong improvement with the addition of imazapyr to glyphosate (84% mortality), glyphosate treatments had titi mortality as high or higher than the triclopyr operational treatment (57% mortality), and that methylated seed oil surfactant improved glyphosate efficacy but might have been antagonistic for combination treatments. Glyphosate and imazapyr cut stump treatments did not provide higher efficacy than the triclopyr standard treatment (60% mortality). Cut stem treatments (targeting rootstocks greater than 1.5 m tall) provided the highest level of control averaging 97, 90, 97, and 80% mortality for glyphosate, imazapyr, combination treatments, and triclopyr standard, respectively. Only directed foliar sprays reduced total groundcover and graminoid cover, with triclopyr treatment giving the least reduction of desired herbaceous groundcover. [ABSTRACT FROM AUTHOR]