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A new problem of macadamia trees (Macadamia integrifolia Maiden and Betche) in Hawaii is characterized by slight leaf chlorosis, followed by rapid leaf browning, and tree death. Ambrosia beetle [Xyleborus affinis Eichhoff and X. perforans Wollastan (Coleoptera: Scolytidae)] infestations and fungal fruiting bodies were present on trees that subsequently exhibited the decline pattern. `Ikaika' was the most susceptible cultivar, and tree death occurred 8.3 ± 2.6Sd months after beetle infestations were detected.

Standards based on fecal indicator bacteria (FIB) have traditionally been used by the U.S. Environmental Protection Agency to determine when recreational waters are contaminated by fecal and sewage inputs. Studies in tropical and subtropical areas, however, have shown that these same standards cannot reliably be used in these environments to determine when waters are contaminated by sewage. This is because soil, sediments, water, and plants have been shown to be significant indigenous sources of FIB in tropical/subtropical climates. In these climates, alternative fecal indicators, such as Clostridium perfringens and F+RNA coliphages, may be more reliable markers of sewage contamination, because these organisms are generally found in low concentrations in the environment. In the State of Hawaii, monitoring data relating to FIB (fecal coliform, Escherichia coli, enterococci) and alternative indicator microorganisms (C. perfringens, F+RNA) in recreational waters has been obtained for the Island of Oahu, but similar data are lacking for other islands within the state. The major goal of this study was to monitor water samples obtained from the Nawiliwili watershed on the Island of Kauai for traditional FIB (fecal coliform and enterococci) as well as alternative fecal microbial indicators (C. perfringens, somatic coliphages, and F+RNA coliphages). Results for FIB concentrations on the Island of Kauai followed a similar trend as data obtained from the Island of Oahu. In addition, in areas like the Island of Kauai where cesspools are prevalent, monitoring for F+RNA and somatic coliphages may provide more reliable data in the detection of subsurface contamination of streams by cesspool waste, which can then lead to the pollution of coastal waters. Finally, genotyping of F+RNA phages obtained from the study sites provided additional evidence that human cesspool contamination was occurring within the Nawiliwili watershed.

Leaf areas of Macadamia integrifolia Maiden & Betche cvs. Kakea and Keaau were estimated by equations involving linear dimensions length and width in second degree polynomials. The equations accurately estimated leaf area at 2 locations for each cultivar.