Both walnut and Gingko trees lose their leaves in the fall when day length starts decreasing. Based on these observations one may conclude that many tree species will lose their leaves in the fall in response to decreasing day length. This statement is an example of:

A wood member is loaded as shown. Using ASD, determine the maximum bending stress in the member. Assume normal temperatures, no incising, and that all loads act in the directions shown. Ignore the weight of the member.Load:PD = 4,500 lbPL = 0 lbPLr = 0 lbPS = 0 lbPR = 0 lbPW = 5,000 lbPE = 7,500 lbQD = 2,500 lbQL = 0 lbQLr = 1,000 lbQS = 1,000 lbQR = 3,000 lbQW = 0 lbQE = 0 lbSpan:L = 12 ft Member size:4 x 6 Stress grade and species:Select Structural Douglas Fir-Larch Unbraced length:lu = L/2 = 6 ft Moisture content:MC < 19 percent 

A wood member is loaded as shown. Using ASD, determine the maximum axial stress in the member. Assume normal temperatures, no incising, and that all loads act in the directions shown. Ignore the weight of the member.Load:PD = 4,000 lbPL = 0 lbPLr = 0 lbPS = 0 lbPR = 0 lbPW = 8,000 lbPE = 5,500 lbQD = 1,000 lbQL = 4,000 lbQLr = 2,000 lbQS = 5,000 lbQR = 0 lbQW = 0 lbQE = 0 lbSpan:L = 14 ft Member size:4 x 12 Stress grade and species:Select Structural Douglas Fir-Larch Unbraced length:lu = L/2 = 7 ft Moisture content:MC < 19 percent 

Use APA Technical Note Q225 entitled Load-Span Tables for APA Structural-Use Panels and ASD procedures to answer the following question.The spacing of rafters in a roof is 16-in. o.c. Roof dead load = 15 psf. Snow load = 47 psf. Roof sheathing is to be an APA rated plywood sheathing, and panels are to be oriented in the strong direction. The load is governed by deflection limits of L/240 for snow load and L/180 for total load. Only consider these limits. Assume multi-span, normal duration of load, dry conditions, and panels 24 inches or wider. Would a panel with a span rating of 32/16 be adequate?

Use APA Technical Note Q225 entitled Load-Span Tables for APA Structural-Use Panels and ASD procedures to answer the following question.The spacing of joists in a floor system is 30-in. o.c. Floor dead load = 12 psf. Floor live load = 64 psf. Floor sheathing is to be an APA rated OSB sheathing, and panels are to be oriented in the strong direction. The load is governed by bending and shear for total load. Only consider these limits. Assume multi-span, normal duration of load, dry conditions, and panels 24 inches or wider. Would a panel with a span rating of 40/20 be adequate?

Use APA Technical Note Q225 entitled Load-Span Tables for APA Structural-Use Panels and ASD procedures to answer the following question.The spacing of joists in a flat roof is 24-in. o.c. Roof dead load = 15 psf. Snow load = 55 psf. Roof sheathing is to be an APA rated plywood STRUCTURAL I sheathing, and panels are to be oriented in the weak direction. The load is governed by deflection limits of L/360 for snow load and L/240 for total load. Only consider these limits. Assume multi-span, normal duration of load, dry conditions, and panels 24 inches or wider. Would a panel with a span rating of 32/16 be adequate?

Use the AWC Manual for Engineered Wood Construction, 2018 Edition to answer the following question. An APA Rated Sheathing panel with a span rating of 32/16 is used with framing that is spaced at 32 o.c. Does the panel require edge support? Assume the panel is 24 inches or wider.

A wood member is loaded as shown. Using ASD, determine the maximum axial stress in the member. Assume normal temperatures, no incising, and that all loads act in the directions shown. Ignore the weight of the member.Load:PD = 5,000 lbPL = 0 lbPLr = 0 lbPS = 0 lbPR = 0 lbPW = 5,500 lbPE = 6,000 lbQD = 1,500 lbQL = 0 lbQLr = 2,500 lbQS = 1,000 lbQR = 1,000 lbQW = 0 lbQE = 0 lbSpan:L = 13 ft Member size:4 x 14 Stress grade and species:No. 1 Douglas Fir-Larch Unbraced length:lu = L/2 = 6.5 ft Moisture content:MC < 19 percent 

Use APA Technical Note Q225 entitled Load-Span Tables for APA Structural-Use Panels and ASD procedures to answer the following question.The spacing of joists in a floor system is 12-in. o.c. Floor dead load = 19 psf. Floor live load = 66 psf. Floor sheathing is to be an APA rated OSB sheathing, and panels are to be oriented in the strong direction. The load is governed by bending and shear for total load. Only consider these limits. Assume multi-span, normal duration of load, dry conditions, and panels 24 inches or wider. Would a panel with a span rating of 40/20 be adequate?

A wood member is loaded as shown. Using ASD, determine the maximum bending stress in the member. Assume normal temperatures, no incising, and that all loads act in the directions shown. Ignore the weight of the member.Load:PD = 4,500 lbPL = 0 lbPLr = 0 lbPS = 0 lbPR = 0 lbPW = 8,000 lbPE = 7,000 lbQD = 2,500 lbQL = 3,000 lbQLr = 500 lbQS = 1,500 lbQR = 0 lbQW = 0 lbQE = 0 lbSpan:L = 6 ft Member size:4 x 8 Stress grade and species:Select Structural Douglas Fir-Larch Unbraced length:lu = L/2 = 3 ft Moisture content:MC < 19 percent