Maturity and Viability of Seed From Squirrel-Cut Pine Cones

1987 ◽  
Vol 63 (4) ◽  
pp. 268-271 ◽  
Author(s):  
T. A. Hurly ◽  
R. J. Robertson ◽  
C. W. Yeatman

The viability of pine seed from cones cached by red squirrels was compared with the viability of seed collected weekly during August and September. Scots pine seed collected during the last three weeks of August exhibited poor but increasing germinability (24.3% – 77.0%), but seed collected in September showed high germinability (95.0% – 99.5%). The strategy of collecting cones before intensive harvesting by squirrels is therefore of limited utility. Scots, red, and jack pine cones recovered from squirrel caches yielded seed of acceptable quality (greater than 80% germinability in 9 of 10 collections). Recovering cones from squirrel caches is a practical and viable strategy in seed orchards and natural forests. We recommend that collections be made within one month of harvesting by the squirrels. Key words: pine seed, seed viability, seed maturity, seed orchard red squirrel management.

1964 ◽  
Vol 40 (1) ◽  
pp. 98-110 ◽  
Author(s):  
J. W. Bruce Wagg

A study was made of the viability of white spruce, Picea glauca, seed obtained from seven cone caches of red squirrels, Tamiasciurus hudsonicus. Habits of the red squirrel, relation of seed viability to cone-caching activities and the relation of viability of seed obtained from the cached cones to the cones on the trees are described.Viability of see from cached cones does not vary between the time squirrels began to cache cones in quantity and the time the last cones are cached. Seed from the cached cones showed a higher percentage of viability than seed of cones collected from trees, because some of the mature seed had fallen from the partially open cones on the trees resulting in an increase in the percentage of undeveloped seed in progressive cone collections.


1979 ◽  
Vol 55 (5) ◽  
pp. 170-174 ◽  
Author(s):  
W. H. Cram ◽  
C. H. Lindquist

Cone and seed maturity of Scots pine (Pinus sylvestris L.) were evaluated for three seed years and several plantations in prairie Canada. Both specific gravity and moisture content provided reliable measures of cone maturity and were directly related to viability of the seed produced. Individual trees were found to differ as to cone and seed maturity for successive harvests in three years. Cones were mature when specific gravity decreased to 1.02 or a moisture content to 38% and produced seed with a high germination capacity even after four years of storage (81 to 95%). Distilled water is recommended for field testing of cone maturity for individual trees. Number of seeds per cone and seed weight were more directly related to cone size than to cone maturity. Neither color of cones nor color of seeds proved reliable measures of maturity.


Author(s):  
Natalia N. Besschetnova ◽  
Vladimir P. Besschetnov ◽  
Nikolai A. Babich ◽  
Vladimir A. Bryntcev

An important moment in the establishment of forestry seed orchards is the formation of their optimal composition, avoiding inbreeding depression in the outgoing seed material which occurs due to crossbreeding between closely related plus trees, the clones of which comprise the orchards. It is possible to minimize the negative effect of inbreeding by considering the hereditary aspect of the heterogeneous seed orchard material. The purpose of our work is to provide a comparative assessment of the formation and lignification of xylem in annual shoots of the plus trees of Scots pine. We investigated the formation and lignification of xylem in the annual shoots of the plus trees of Scots pine (Pinus sylvestris L.), found in natural forests in the Nizhny Novgorod region of the Russian Federation. Their vegetative progeny were cultivated in the clone archive stationed in the same region. Analyzing the one-type of the 1-year shoots, the time that the shoots were cut from the branches corresponded to the presence of plants in the characteristic phenological phases of seasonal development. A histochemical study of xylem was conducted, using the qualitative reactions of phloroglucinol to lignin. The power of xylem development was estimated by counting, in the radial direction, the cell rows from the core to the cambium in the microscope’s field of view. A significant differentiation of plus trees was revealed in a complex of signs characterizing the level of xylem development and the degree of xylem cell lignification in the tissues of annual shoots. Phenotypic differences in the physiological state of plus trees appeared given a leveled ecological background, indicating their genotypic determinism. This was confirmed by an analysis of variance. The share of the influence of differences between the proper plus trees was between 25.16%  ± 8.91% and 53.98%  ± 5.48% of the total phenotypic variance of the signs of the seasonal state of xylem. Factor analysis was used to reduce the number of considered indicators of xylem physiological state. The results allowed a cluster analysis to be carried out on the basis of the normalized values of the initial xylem features as well as the principal components derived from them. The association of plus trees was done on the basis of the similarity of the multidimensional estimates of xylem seasonal condition. The objects that were the most remote from the others were identified. This information provides a reasonable approach to the formation of an assortment of Scots pine seed orchards.


1988 ◽  
Vol 120 (12) ◽  
pp. 1113-1121 ◽  
Author(s):  
Y.H. Prévost ◽  
J.E. Laing ◽  
V.F. Haavisto

AbstractThe seasonal damage to female reproductive structures (buds, flowers, and cones) of black spruce, Picea mariana (Mill.) B.S.P., was assessed during 1983 and 1984. Nineteen insects (five Orders) and the red squirrel, Tamiasciurus hudsonicus (Erxleben), were found feeding on these reproductive structures. Collectively, these organisms damaged 88.9 and 53.5% of the cones in 1983 and 1984, respectively. In the 2 years, Lepidoptera damaged 61.8% of the cones in 1983 and 44.4% of the cones in 1984. The spruce budworm, Choristoneura fumiferana (Clem.), and the spruce coneworm, Dioryctria reniculelloides Mut. and Mun., were the most important pests. Cones damaged by Lepidoptera could be classed into three categories: (a) severe, yielding no seeds; (b) moderate, yielding 22.3 seeds per cone; and (c) light, yielding 37.5 seeds per cone. Undamaged cones yielded on average 39.9 seeds per cone. Red squirrels removed 18.8% of the cones in 1983 and none in 1984. The spruce cone axis midge, Dasineura rachiphaga Tripp, and the spruce cone maggot, Lasiomma anthracinum (Czerny), caused minor damage in both years. Feeding by spruce cone axis midge did not reduce cone growth significantly or the number of viable seeds per cone, but feeding by the spruce cone maggot did. During both years new damage by insects to the female reproductive structures of the experimental trees was not observed after mid-July. In 1983 damage by red squirrels occurred from early to late September. In 1984 damage to cones on trees treated with dimethoate was 15.6% compared with 53.5% for untreated trees, without an increase in the number of aborted cones.


1977 ◽  
Vol 34 (12) ◽  
pp. 2369-2373 ◽  
Author(s):  
Doris Fraser Hiltz ◽  
D. H. North ◽  
Barbara Smith Lall ◽  
R. A. Keith

Refrozen silver hake (Merluccius bilinearis), processed as fillets and minced flesh after thawing of stored round fish that had been frozen within 14 h of capture, underwent rapid deterioration during storage at −18 °C compared with once-frozen control materials from the same lot of fish. The estimated maximum storage life of silver hake refrozen as fillets after 3 and 6 mo storage of the round fish at −25 °C was reduced to about 4.5 and 1 mo, respectively, from 10 mo for once-frozen control fillets. Quality of the refrozen materials immediately after thawing and refreezing was similar to that of the round-frozen fish, except after 6 mo, where some initial deterioration occurred, particularly in minced flesh. Minced flesh was more unstable in frozen storage than fillets. In all once- and twice-frozen materials, formation of dimethylamine occurred concomitantly with decrease in protein extractability. Round-frozen fish underwent no loss in protein extractability during 6 mo storage at −25 °C, but some lipid hydrolysis occurred. These results suggest that the freeze–thaw–refreeze process as applied to silver hake will yield a final product of acceptable quality provided that storage of the round fish does not exceed 3–4 mo and that the refrozen materials are marketed within a month after processing. Key words: silver hake, Merluccius bilinearis, refrozen storage, dimethylamine, minced flesh


2021 ◽  
Vol 102 (3) ◽  
Author(s):  
Akbar Dastjerdi ◽  
David J. Everest ◽  
Hannah Davies ◽  
Daniela Denk ◽  
Roland Zell

Dicistroviruses are single-stranded RNA viruses in the family Dicistroviridae. The viruses have mainly been detected in arthropods and are the cause of several devastating diseases in many of these species such as honeybees. Increasingly, dicistroviruses have also been detected in both mammalian and avian species in faeces, blood and liver, but with unconfirmed pathology. Here, we report a novel dicistrovirus detected in the intestinal content of a captive red squirrel with enteritis along with the disease history, pathology and genomic characterisation of the virus. Virus particle morphology resembled those of picornaviruses with a diameter of 28–32 nm but failed to be detected using a mammalian/avian pan viral microarray. Next-generation sequencing confirmed a dicistrovirus having a typical dicistrovirus genome organization, but with the polyprotein 1 being shorter by about 100 amino acids, compared to that of other dicistroviruses. Phylogenetic analysis of ORF1 and ORF2 sequences clustered the virus with two yet unassigned dicistroviruses detected in Gorilla gorilla and a freshwater arthropod and likely to be designated to a new genus. Our data further highlights the ever-growing diversity of dicistroviruses, but the clinical significance of the virus in mammalian species and particularly red squirrels has yet to be established.


2011 ◽  
Vol 56 (No. 8) ◽  
pp. 405-408 ◽  
Author(s):  
A. Aydin

The brachial plexus in adult red squirrels (Sciurus vulgaris) was found to be formed by the rami ventralis of C5, C6, C7, C8. A thin branch of C5 and C6 constituted the cranial trunk, and the caudal trunk was formed completely by the rami ventralis of C7 and C8. Thus, in squirrels, the spinal nerves which form the brachial plexus and the joining of these spinal nerves to each other differ from other rodents and mammals.


2006 ◽  
Vol 138 (6) ◽  
pp. 888-896 ◽  
Author(s):  
Ward B. Strong

AbstractManagement of Leptoglossus occidentalis Heidemann in lodgepole pine (Pinus contorta var. latifolia Engelm.) seed orchards of British Columbia, Canada, would be improved with knowledge of its damage potential at different times of the growing season. Mesh insect-exclusion bags were placed over cones, and adults or nymphs of L. occidentalis were enclosed in different bags for 9 periods of 10 to 38 days between 6 May and 17 September 2004. Feeding by adult females between 6 May and 28 May reduced total extractable seeds, a result of ovule damage before fertilization. Reduction in the number of filled seeds per cone was highest between 6 May and 29 June, with each adult female reducing yield by approximately 1.7 seeds per day. Between 29 June and 10 August, each adult female reduced the number of filled seeds per cone (seed set) by 1.0 to 1.25 per day. Seed set reduction declined to approximately 0.25 filled seeds per adult female per day after 10 August. Third to fifth instars caused seed set reduction between 0.6 and 1.2 filled seeds per cone per nymph feeding day from 29 June to 10 August. Utilizing these findings would improve management of L. occidentalis in a commercial seed orchard setting.


2013 ◽  
Vol 59 (No. 10) ◽  
pp. 377-387 ◽  
Author(s):  
O. Vanek ◽  
Z. Procházková ◽  
MatějkaK

Genetic structure, diversity and clonal homogeneity were determined on the basis of the isozyme gene markers in a model Scots pine seed orchard in the north-eastern part of the Czech Republic that originated from natural forest regions NFR 28 and 29 (Jesen&iacute;ky Mts.) and the 2<sup>nd</sup> and 3<sup>rd</sup> forest altitudinal zones (FAZ). Clone and ramet crop variation for the 2009&ndash;2011 period was assessed. Comparing the loci measured also in two pine orchards in central Slovakia, a similar proportion of homogeneous clones but considerably lower expected heterozygosity were found out for most of the measured isozyme loci. Heterozygosity of the investigated orchard did not change considerably after the exclusion of alien and wrongly placed ramets. No difference in average cone production between clones originating from different NFR was observed. Verification of the clone identity of seed orchards managed in a certain way can be suggested with the subsequent removal of alien ramets.


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